This is mostly intended to help with the collectibles, though at times I will point out things such as where you can get some free weapons.
Note that I won't be including the misc treasures (Spinels, Velvet Blues, and Emeralds), as there are over 100 of them and they are found everywhere.
I have tried to include most "points of no return", but it's possible I may have missed some due to not backtracking much. It's advisable to grab these items on your first visits to places anyway, so it shouldn't matter too much.

Also a warning: Two Yellow Herbs and two treasures will be unobtainable on Easy Mode, as the areas/sequences that contain them are skipped. This is fine, as there are two more yellow herbs than are needed (meaning Easy has the exact amount required) to fully max both Leon and Ashley's health, and treasure is only for selling.

There are also a few other pieces of general advice that will be useful on a playthrough:

• When upgrading a weapon's Ammo Capacity, it will also act as a free ammo refill. So it's wise to use up all the ammo in the current clip (without reloading) before upgrading its capacity. This also applies to Exclusive Upgrades that affect capacity, such as the Striker, which will give you 100 free shells if you get the upgrade while empty.
  
• Shooting crows and birdnests will often give you useful items or more money. If you see a group of crows, a flashbang will make easy work of them, especially if they're on the ground. However, Chickens should be kept alive, as they can occasionally drop eggs, which act as healing items, or throwables to make enemies flinch.
  
• When doing the Blue Medallion sidequest in the village, shooting 10 medallions and speaking to the Merchant will allow you to purchase the Punisher handgun for free. However, if you instead shoot all 15 before redeeming the gun, it will come with a free firepower upgrade. If you've already redeemed the gun before getting all 15, you'll miss out on this.
  
• Stronger enemies such as those wielding chainsaws, or some of the red-hooded cultists will drop a lot of money (or sellable items) upon death, so try to kill them if you're able to.
  
• Paintings of the Hooded Man Saddler (mainly in Chapter 3) can occasionally be interacted with to reveal money behind them.

I've done a similar guide for the remake's version of Separate Ways here: https://steamproxy.net/sharedfiles/filedetails/?id=3537083429
I may make a version for the main story of RE4:Remake, but no promises!

• Yellow Herbs raise your maximum HP, but can only be used when mixed. If mixed with a single green herb, it will increase your maximum HP and heal you a small amount. If mixed with a green and red herb, it will increase your maximum HP (the same amount) while also fully healing you.
  
• It may be useful to keep the G+R+Y herb combos in your attache case until you need healing, rather than using them straight away.
  
• Two yellow herbs (One in Chapter 3-2, and one in Chapter 4-1) will be unobtainable on Easy difficulty, as the sections where you obtain them are skipped.
  
• There are 27 yellow herbs in the game (25 on Easy mode). It takes 20 to max out Leon's HP, and 5 to max out Ashley's. So you can miss two and be fine (unless you're playing on Easy), though if you do find any extras, you can sell them.
  
• Selling yellow herbs can be very profitable. On their own, they sell for 3,000₧. Combining them with other herbs will increase their price, up to 10,000₧ when combined into a G+R+Y mixture.
  
• It is suggested to focus on increasing Leon's maximum HP, rather than Ashley's. (At least on Easy/Normal. I'm not too sure about Professional difficulty) In fact, by the end of the game you can probably sell the yellow herbs you would have given Ashley.

Yellow Herb #1
You can find this Yellow Herb in the Southwest, in a box behind the stable with the cow inside. Use your knife to break open the box, and the herb will be yours. There should also be a red herb nearby, useful for combining.
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There are 15 Blue Medallions in Chapter 1 that can be shot for a reward later on. 7 of them can be found on the farm. But first, there are two Treasures to obtain.

Treasure: Pearl Pendant (10,000₧)
To the right of the shed with the typewriter inside, you'll find a well with a necklace hanging above it. Before you shoot down the necklace, make sure to shoot the wooden beam to cover the water.Failure to do so will cause the pendant to become a Dirty Pearl Pendant, which only sells for 1,000₧
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Treasure: Beerstein (Combinable)
Climbing the ladder in the big white barn, you'll see a window to your left. Jump out of it, then jump down to the small area immediately ahead of you. You'll see a box you can break with your knife containing the Beerstein. Don't sell this yet, as it can be combined with three later treasures to sell for a much higher price. (At the moment it sells for 3,000₧, but when completed, will sell for 20,000₧)
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Blue Medallions #1-7
There are 15 Blue Medallions in Chapter 1 that can be shot for a reward later on. 7 of them can be found on the farm.

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Medallion #1 can be seen as soon as you enter the area, hanging from a tree.


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Medallion #2 is found in the upper window of the big greenish barn.


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Medallion #3 is hanging from a tree behind the barn where you found the second medallion.

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Medallion #4 is behind the big white barn, right at the top.

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Medallion #5 is in the top window at the front of the big white barn.

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Medallion #6 is hanging from the windmill in the fenced off area to the Northeast.

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Medallion #7 will be hanging from the wooden barricade in the fenced off area to the Northeast.

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After Leon escapes the boulder, you'll find yourself in a small tunnel leading to a deserted village. The tunnel has two shining points on the ceiling that you can shoot down to get some Spinels. This guide won't cover the small miscellaneous treasures such as spinels as there are over 100, so look out for these shining spots.
Also, please note that this area will be blocked off if you progress too far beyond Chapter 1-3, so make sure to grab the next treasure now.

Treasure: Red Catseye (Combinable)
Before entering the house to the Northwest, look for the tree to the right of it and shoot down the bird's nest to obtain a Red Catseye. This can be combined with the Beerstein. But don't sell it yet, as there are two more Catseyes you can obtain.

Please note that the following two areas will be blocked off if you progress too far beyond Chapter 1-3, so make sure to grab these now.

As soon as you exit the house at the start of the chapter, you can go behind it to meet up with the Merchant. Feel free to sell your Pearl Pendant and any Spinels you've picked up, but again, do not sell the Bearstein/Catseye as you can combine it with other catseyes later to get a higher selling price.

Yellow Herb #2
Just before you enter the two insignia-halves into the door at the end of the valley, check the locker inside the shack to the left for another yellow herb.
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Treasure: Elegant Mask (Combinable)
You'll see the Elegant Mask as soon as you enter the building, but you won't be able to grab it from this room. In the room after the one filled with enemies and bear traps, turn to the left and you'll see the mask once again. Use your knife to break the wooden boards covering the window, then enter and grab it. Don't sell this yet, as you can place three gems inside to increase its value.
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Treasure: Brass Pocket Watch (10,000₧)
After you climb out from the well, you'll see another water basin to your left. Like last time, shoot the wooden beam to cover the water, then shoot down the Brass Pocket Watch. If you fail to shoot the beam and let the pocket watch fall into the water, it'll only be worth 1,000₧.

As you leave the house at the beginning of the chapter, you'll be met with another Chainsaw wielding villager. If you manage to kill him, he'll drop a Ruby worth 10,000₧.
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Treasure: Elegant Headdress (10,000₧)
After passing through the Village Square once again and entering the door, you'll climb down a ladder into a cave. On the ceiling, you'll see a lamp. Shoot it down (from a distance) and it'll reveal three shining spots on the ceiling. Two will be spinels, and the other will be an Elegant Headdress.

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The merchant can be found at the end of the cave, and he'll inform you of his Blue Medallion Challenge.
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The final 8 medallions can be found here, but to make things easier, take care of the enemies first, and grab the next treasure while you're there.

Treasure: Green Catseye (Combinable)
Behind the church you'll find a device with various symbols. Interacting with this and dompleting the puzzle will get you the Green Catseye, which can be combined with the Beerstein. The Beerstein should now have two catseyes in it, so you'll only have to find one more.
If you need a hint with the puzzle, try checking the tombstones.
If you just want the solution, it's 3, 3, 3, 4, 4, 4, 3.

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Blue Medallions #8-15
The final 8 medallions can be found here. While you'll get a new handgun for free as a reward for shooting 10 in total, make sure to only claim your reward from the Merchant once you've obtained all 15, as doing so will get you a free firepower upgrade for your new weapon.
If you were to shoot 10 medallions, get the gun, then shoot the last 5, you'll have missed out on the free upgrade.
For maximum ammo efficiency, try not to reload after shooting the medallions, as you'll be getting rid of this handgun soon, so any bullets in the gun itself will be lost.
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Medallion #8 is hanging from a tree to the left of the small shack in the West of the graveyard.

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Medallion #9 is hanging from a tree in the actual graveyard.

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Medallion #10 is also hanging from a tree in the graveyard.

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Medallion #11 is hanging from a tree to the left of the church itself.

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Medallion #12 is hanging on the top of the church. You can reach it from the area where you found the Green Catseye.

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Medallion #13 is below the wooden platforms leading to the West. Jump over the first one then turn back around to see it.

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Medallion #14 is hanging up above the wooden platforms to the West.

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Medallion #15 is also hanging below the wooden platforms.

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With all 15 medallions, you can now head back to the Merchant in the cave and purchase the Punisher handgun. Feel free to sell your original handgun at this point. If it still has ammo in it, it may be a good idea to use it up on any enemies ahead (make sure not to reload), and then sell it.
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There are no yellow herbs or major treasures here (at the moment), but there will be a group of crows in the center of the area. Use a flashbang (or other grenade if you're out of flashbangs) to kill them all and obtain a lot of money and some items. If you miss any, you can try shooting them, or leave and re-enter the area to reset the crows that weren't killed.
You'll also find a Spinel in a wheelbarrow to the Northwest.
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Treasure: Antique Pipe (10,000₧)
By the second set of boardwalks, you'll see a bird's nest in a tree. Shoot it down to get the Antique Pipe.

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Treasure: Gold Bangle w/ Pearls (10,000₧)
As you go down the hill towards the lake, shoot the bird's nest to get the Gold Bangle with Pearls.

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Yellow Herb #3
There will be two shacks near the bottom of the hill by the lake. The first one will contain a wooden box you break with your knife to get the Yellow Herb.

Treasure: Green Gem (Combinable)
As soon as you leave the building, instead of turning to the right and progressing the story, get back on the boat and take it all the way the cave in the Northwest of the map. Push the box to the left of the Merchant's shop, then climb up to the roof. After pushing a couple more boxes, you'll find the Green Gem inside a breakable barrel.
You can combine this with the Elegant Mask, though you'll still need two more gems before you can get the best selling price for it.

While you're up there, you can use your knife to swipe at the hanging lantern and knock down a Spinel.
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Treasure: Amber Ring (10,000₧)
Before you finish solving the Waterfall puzzle, go to the middle section and shoot down the Amber Ring.

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Yellow Herb #4
After (or during, if you're quick) your fight with El Gigante, you can grab the Yellow Herb from the wheelbarrow in the Northwest of the arena.

There aren't any treasures in this Chapter, just a yellow herb. But on your way to get it, you'll pass through a few previous areas again. While some items will have been replaced with new ones, you should still be able to get some things from before if you missed them.

Yellow Herb #5
While you're defending the cabin, there will be a Yellow Herb on a counter downstairs. You should also find a Red Herb close by. If you need healing during the defense, combining a Green, Red, and Yellow herb will give you a full heal on top of boosting your maximum health.

Once you've cleaned out the cabin and done any business you needed to with the Merchant, you'll have a choice to make. Kinda.

There are two paths you can take to progress here, however each one will contain a Gem for your Elegant Mask (and of course, each one will have a variety of loot.
So it's up to you whether you want to go through one path to be safer, or go through one, come back, then go through the other to get the most you can.
Neither paths contain a Yellow Herb, so this is purely for money (and ammo you'll find along the way).
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After fighting your way through part of the camp, you'll face a couple of Chainsaw enemies. One will drop a key to the nearby door, while the other will drop a Ruby that sells for 10,000₧.

Treasure: Red Gem (Combinable)
Once you've gone through the door using the key dropped by the Chainsaw Sister, take a right into the wooden building with the trap door inside. Before going through the trap door, use your knife on the window and break the barrels down the path to obtain the Red Gem. You can combine this with the Elegant Mask.
You should now have a Green and Red gem inside the mask. Once you get the purple gem from the other path, you are free to sell the Elegant Mask for 20,000₧. If you're not planning on getting the purple gem, the Mask will still sell for 15,000₧ with just the Green and Red ones inside.

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Walking forward, you'll begin a miniboss fight with another El Gigante who will drop 15,000₧.
Treasure: Purple Gem (Combinable)
You'll notice that this area is split into three sections, with two doors. Go to the second door, then turn around. Looking up, you should see a bucket that's shining. Shoot the bucket to get the Purple Gem. You can combine this with the Elegant Mask.
If you didn't take the left path, you should now have a Green and Purple gem inside the mask. Once you get the red gem from the other path, you are free to sell the Elegant Mask for 20,000₧. If you're not planning on getting the red gem, the Mask will still sell for 15,000₧ with just the Green and Purple ones inside.

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Treasure: Yellow Catseye (Combinable)
After riding the lift down to the bottom, take the stairs partially down, but take the wooden walkway instead of going down fully. In a cave with enemies, you'll find a treasure chest with a Yellow Catseye inside.
You should now have all three Catseyes which can be combined with the Beerstein. No need to head back up the lift to the Merchant, just keep going down those stairs and you can sell it here instead.

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Yellow Herb #6
Inside the Slaughterhouse you'll be faced with another boss fight. A yellow herb can be found up the ladder on the windowsill. It's fine if you kill the boss first, just make sure you grab it before you leave the building.

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Note: In this chapter, you'll likely find a bunch of paintings of Saddler. Interacting with them may reveal hidden compartments filled with money.
You'll also begin to find "Velvet Blue" gems. These are like Spinels, where they are numerous, aren't combined with anything, and can just be sold immediately.


Yellow Herb #7
Avoiding or destroying the catapults, take the stairs up and run up to the small stone shack. Alongisde an enemy, there will be a small treasure chest inside containing the Yellow Herb.

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Treasure: Gold Bangle (8,500₧)
To the left outside of the shack where you found the Yellow Herb, you'll find another treasure chest containing the Gold Bangle.

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Treasure: Purple Gem (Combinable)
Walk forward in the hall until you meet Salazar. Once the cutscene ends, walk up the stairs a bit more and turn around. Look up and shoot the shimmering spot to get a familiar looking Purple Gem. Hold onto this, as we'll be finding another Elegant Mask for it later.

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Yellow Herb #8
Just before the room with the two fire-breathing horse statues, you'll see two wooden barrels. Break them with your knife to reveal the Yellow Herb.

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After the water room, you'll be in the temple. There aren't any treasures here aside from the Spinel behind one of the statues coming from the ceiling. However, you will find the Merchant's Shooting Gallery here. There are some notes on it below. Once you've tried it out, head back to the temple and walk down the corridor to progress to the next chapter.

You can earn a bunch of money by playing the Merchant's Shooting Range through the blue door to his left in the Temple. There are four games in the Shooting Range, though only Game A will be available at the moment. More will unlock for each Shooting Range you find until you have A through D unlocked.

If you are playing on a New Round (New Game+) and have obtained the rewards in a previous round, you won't earn the money again for completing the shooting range.

Also, if you're playing the Oculus Quest VR version, the shooting range still exists, however for some reason there is no monetary reward for completing it. You just obtain the bottlecaps. So other than the challenge and looking at the various bottlecaps in your collection, there is no reason to play the Shooting Range in the VR version.

Each game has a total of 6 prizes to win, for a total of 24 once you get to all the Shooting Ranges.
Choose either Rapid-Fire weapons or Sniping weapons, it's up to you. You won't get extra prizes for completing a game with one type of weapon and then the other, it's simply preference.

Shooting enemies in the head will earn double points, and shooting 5 enemies in a row without missing will make Salazar's head appear at the back, which will give you even more points.

Note: Enemies first seen in this area will drop colored Eye gems. Green being the most common, red being uncommon, and blue being the rarest. You can combine these with a treasure called the "Butterfly Lamp", which the game has two of. So make sure to keep two of each color, but feel free to sell the rest.

Yellow Herb #9
While you're down in the waterway, you'll come across four jail cells next to the pit of water you have to drain. The Yellow Herb will be in one of these cells, next to a body.

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Treasure: Butterfly Lamp (Combinable)
The Butterfly Lamp can be found in the room where you turn the valve to drain the water.
As stated above, this can be combined with the Red, Green, and Blue Eyes dropped by the Novistadores (the bugs you've been fighting in this area). Make sure to keep at least two of each color, as you'll find another Butterfly Lamp later in the game.

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Treasure: Iluminados Pendant (12,000₧)
You'll soon be back in the main temple hall where you'll see a cutscene of some cultists chanting. Killing the one in red will cause them to drop an Illuminados Pendant. The black-robed cultists will drop Spinels.

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Treasure: Elegant Mask (Combinable)
When you're done looting the cultists, climb back up the ladder and jump across the room using the chandelier. Jump across a second chandelier to find a treasure chest encased in glass. Smash it with your knife to get another Elegant Mask. If you got the Purple Gem in the previous chapter, you can combine it now.

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Yellow Herb #10
After a cutscene with Salazar, you'll be forced to fight a bunch of cultists to obtain the Goat Ornament required to progress the story. Connected to this room is a staircase in the Northeast that can be accessed from either floor. At the top of this staircase is your next Yellow Herb.

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Aside from little treasures like Spinels and Velvet Blues, there aren't any treasures/yellow herbs to be found here yet, as the door is locked. However you'll have a brief window of time in Chapter 4-1 where you can come back and get past the door. Make sure to remember it, as you'll be able to get a powerful weapon for free as well as another Treasure.

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Note: On Easy difficulty, the garden maze will be unreachable along with anything contained within.
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Yellow Herb #11
In the Southwest corner of the maze, you'll find another Yellow Herb.


Treasure: Red Gem (Combinable)
Close to the yellow herb is a treasure chest contaning the Red Gem. You can combine this with the Elegant Mask, and if you collected the Purple Gem in the previous chapter, you should only have the Green Gem left to find.

There are no Yellow Herbs to be found in this chapter.

Treasure: Mirror w/ Pearls & Rubies (12,000₧)
Once you've used the two Moonstone Halves to enter the bedroom, you'll meet the Merchant once again in a room next to the bed. The Mirror w/ Pearls & Rubies will be inside a closet in this room.

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Treasure: Hourglass w/ Gold Decor (12,000₧)
During or after your fight with a Garrador in a cage, you'll be able to get the Hourglass from the Treasure Chest in the middle of the cage.

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This room doesn't contain any treasures, but instead holds the most beautiful piece of art there is:
A Free Rocket Launcher.

This will take up a massive 16 spaces (8x2) in your attache case, but if you want to sell stuff to make space, the Merchant is in the next room.
Note that it can only be fired once. There are no ammo pickups for rocket launchers. As soon as you've shot one, it'll disappear forever.
You can also buy these from the Merchant for 30,000₧, which can be pretty expensive, but keep in mind that they have the power to defeat any enemy in a single shot (including some bosses if you land a direct hit).
You can pick this up and sell it for 15.000₧, or keep it for a boss encounter of your choice.
My recommendation would be to use it on the scorpion-like Verdugo boss in the tunnel at the end of Chapter 4-1.

(And just as a side-note, this isn't the "free powerful weapon" mentioned in the previous section of the guide. That one's still to come.)

Yellow Herb #12
After a brief defense section, you'll be playing as Ashley. In the very first room, you'll find a Yellow Herb to the left.
As mentioned near the beginning of the guide, Ashley probably doesn't need the Yellow Herbs on Easy/Normal, but that is purely my suggestion.
If you decide not to use it on her, just keep it in your inventory, as you'll have an opportunity to transfer Ashley's items to Leon soon. Leon is also able to use the Yellow Herbs on Ashley, so there's no rush to make a decision.

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Treasure: Gold Bangle (8,500₧)
Once you've finished the dreaded sliding tile puzzle, the Gold Bangle will be in a treasure chest in the room that opens up.

If you need help with the sliding puzzle, the solution is to go counter-clockwise starting from the middle-left piece. Imagined as a phone's number pad, it'll be 4, 7, 8, 9, 6, 3, 2, 1, 4, 7, 8, 9
If you want to reset the puzzle, travel through the loading screen to the previous area then come back.

You'll regain control of Leon in this chapter. Transfer any items Ashley found to Leon's inventory when given the opportunity.
Before you do ANYTHING else, you're gonna want to do some backtracking to get a powerful free weapon and another treasure. I'd recommend keeping 8 (2x4) slots free in your inventory. You've gotta go all the way back to the Western Castle Wall, the area just before the Garden maze. You can open a shortcut there via the dining hall. The passage to the south of where you shot the wine on the painting will lead to the Western Castle Wall.
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Treasure: Elegant Perfume Bottle (10,000₧)
Free Weapon: Broken Butterfly (8 slots, 2x4)
Back by the fountain, you can interact with the door only to find that it's locked. Interact with the window beside it to give Ashley a boost into the room, where she can open the door for you.
Inside you'll find a bunch of treasure chests. One contains an Elegant Perfume Bottle, and another contants the "Broken Butterfly" revolver, a powerful weapon that uses Magnum Rounds.

If you don't want to use the Broken Butterfly, you can sell it for 19,000₧.
Also, make sure Ashley is following you after boosting her into the room, as she often gets set to "wait" mode after doing so.
And with that, you can carry on from where you left off.
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Treasure: Iluminados Pendant (12,000₧)
There will be two fire-breathing dragon statues moving around on both the left and right of this room.
If you're able to destroy them, you'll be rewarded. The first will reveal a chest with 5,000₧ inside, while the second will reveal a chest with an Illuminados Pendant.
The easiest way to destroy them is to shoot the cultists operating them, although it's possible to shoot the bulky parts of the chains carrying them, though they are harder to destroy compared to the cultists who die in one hit.

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After getting the Lion Ornament in the Dragon Room, you'll take a ride back to the Audience Hall to place the three ornamanents in their respective slots. If you missed the Purple Gem in Chapter 3-1, this will be your other opportunity to grab it.
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There are a lot of different ways to go from the lobby, including a room where the Merchant has set up shop, along with a door to his shooting range. Accessing this shooting range will unlock "Game B", meaning you can earn 6 more bottlecaps and some prize money!
Note that when playing on Easy difficulty, the Eastern room will be inaccessible, which means the Yellow Herb found there is also unobtainable.
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Yellow Herb #13
If you look to your right immediately as you enter the lobby, you should see the next Yellow Herb sitting on a table. This is unobtainable on Easy difficulty.

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Treasure: Green Gem (Combinable)
Heading North from the Lobby, you'll see four statues, each holding a shimmering object. Three of them contain smaller treasures, but the one that's second-closest to you is holding the Green Gem.
You can combine this with the Elegant Mask. By now, you should have all three gems combined with the mask, so you can sell it for 20,000₧.

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Treasure: Elegant Chessboard (13,000₧)
Taking the golden door the West room from the Lobby, you'll enter a room where you have to push some statues. When you're done with this whole sequence and have picked up the Queen's Grail required to progress the story, check the room for a small cabinet containing the Elegant Chessboard.

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Treasure: Butterfly Lamp (Combinable)
Before opening the large door to the Ballroom, jump through the window to the right and climb the ladder. Follow the path round the building and open up the treasure chest to obtain the second Butterfly Lamp.

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Treasure: Blue Eye (Combinable)
You'll should get a lot of Eye Gens from killing the Novistadores in this room. As a reminder, you need two of each color (the common Greens, uncommon Reds, and rare Blues) to combine with the two Butterfly Lamps in the game, both of which you should already own.
While the Blue Eyes are rare, you can get one guaranteed by shooting the giant nest hanging from the ceiling. After taking enough damage, it will drop a bunch of Eye Gems, one of which will be guaranteed to be Blue.

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Treasure: Gold Bangle (8,500₧)
Note: This treasure is unobtainable on Easy Mode.
After turning the bridge at the clock tower, two wave of enemies will spawn as you go outside and cross it. During the second wave, an enemy with a Goat Mask will be with them. Kill him and he'll drop a Gold Bangle.

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Yellow Herb #14
After going down the pit, check the ground for a ton of items, including another Yellow Herb.


Treasure: Crown (Combinable)
On the other side of the pit will be a corpse holding a Crown. Once it's combined with other items, it'll sell for a massive 48,000₧, the highest selling price of any treasure in the game.

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Treasure: Crown Jewel (Combinable)
You have a choice to make. The boss in this area will drop the Crown Jewel, which can be combined with the crown.
However, the boss is optional, and if you stall for four minutes, you can leave the area without defeating it.
If you miss this treasure, you can still combine the Crown with another item to sell it for 27,000₧, but having both items combined with the Crown will let you sell it for 48,000₧.
You wouldn't happen to still have that Rocket Launcher taking up space in your attache case, would you?

You'll be fighting a few more Chainsaw Villagers soon. Keep in mind that they can drop Rubies, which sell for 10,000₧!
There are no Yellow Herbs to be found in this chapter.
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The Merchant has another shooting range down here, which means Game 3 is now unlocked. Try to get all 6 bottlecaps to get that prize money (unless you're playing the VR version or you've already earned it due to being on New Game+).
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Treasure: Eye Gems (Combinable)
After fighting your way through the Mine and the Furnace, you'll be in a big cave filled with Novistadores flying around.
Shooting them while they're flying will instakill them, but they die while flying over the pit, you won't be able to retrieve any of their loot, so make sure they're either flying over solid ground or have landed before attacking.
This is your last opportunity to get Eye Gems from them, so if you haven't finished combining gems with your Butterfly Lamps after this point, you should just sell the lamps and leftover gems as they are.

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Treasure: Royal Insignia (Combinable)
Before interacting with the coffin to leave, pick up the Royal Insignia in front of it. Combine it with the Crown and Crown Jewel (if you got it in Chapter 4-1), and you'll now be able to sell it to the Merchant, who will buy it for a high price.
If you accidentally activate the coffin before picking it up, you can still grab it at the beginning of the next chapter.

Unless you plan on going back down to fight more Novistadores, I'd suggest you finish combining your Eye Gems with your Butterfly Lamps as best you can, then sell them and any gems that remain, as you won't be finding any more. Even if you weren't able to complete both Butterfly Lamps, they'll still fetch a decent price. Make sure to sell that Crown too, now that you have the Royal Insignia (and hopefully the Crown Jewels)!

Treasure: Staff of Royalty (20,000₧)
As you enter the main area of the Underground Ruins, you'll see a small staircase leading down near the entrance. At the bottom you'll find a coffin, which you can interact with to obtain the Staff of Royalty.

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Yellow Herb #15
In the room where you obtain the Key to the Mine, break a barrel in the corner to find another Yellow Herb.

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Yellow Herb #16
When you reach the tower you'll have a cutscene with Salazar. Once it ends, instead of taking the stairs to your right, head to the back of the room and go behind the boxes to the left to find a treasure chest containing a Yellow Herb.

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Treasure: Gold Bangle (8,500₧)
After taking an elevator ride to the top of the tower, you'll run around the outside before finding another elevator. But before taking this one, look to your right and drop down to open a treasure chest containing a Gold Bangle.

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Starting in this chapter, you'll be able to find Emeralds. Like Spinels and Velvet Blues, they are generic treasures that don't combine with anything, so feel free to sell them immediately.

Treasure: Golden Lynx (Combinable)
After completing the mirror puzzle and climbing up the cliff a bit, you'll be in a new area. There will be some enemies outside, but head into the cave to the right and blow up the explosive barrel to break open a wall, revealing a treasure chest containing the Golden Lynx. This can be combined with three jewels you'll be finding later.

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Treasure: Red Stone of Faith (Combinable)
In the room where you first encounter the large hammer-wielding foes, go downstairs and open the case containing the Red Stone of Faith. This can be combined with the Golden Lynx.


Yellow Herb #17
In the same room, walk behind and into the wine cellar, where you'll find a Yellow Herb inside a wooden barrel.

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There are no major treasures or yellow herbs to be found here, but ther Merchant has set up another Shooting Range. The fourth and final game will be available now, so make sure to get 6 points to get all the bottlecaps and the prize money.
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Treasure: Brass Pocket Watch (10,000₧)
Before heading up the stairs, check the room in front of you to the left. Inside you'll find a typewriter, as well as breakable box containing a Brass Pocket Watch.

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No treasures here, but you will pick up an infrared scope that'll be useful against the new enemy type, however it can only be used alongside the Rifle or the Semi-Auto Rifle. If you're not using either of these weapons and don't plan to, you can sell the scope for 10,000₧, freeing up the awkward 3 slots it takes up in your attache case.
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Yellow Herb #18
This one is pretty hard to miss. After leaving the crane room, you'll see this Yellow Herb sitting on a table.

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Yellow Herb #19
After obtaining the Storage Room Keycard the enemy was carrying, instead of heading back the way you came through the Northwest door, take the door to the Southeast to meet up with the Merchant and find another Yellow Herb in one of the wooden barrels next to him.

You can take the lift up to find a green herb and some shotgun shells, as well as seeing a tiny cutscene. But otherwise, this area is completely optional.

Yellow Herb #20
After Ashley crawls under the shutter and opens the gate for you, you'll see this Yellow Herb directly ahead of you. If you need to make space for it, the Merchant is in the room just to the right.

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Treasure: Green Stone of Judgement (Combinable)
In the Merchant's room after dealing with bulldozer, open the case to find the Green Stone of Judgement. This can be combined with the Golden Lynx. One stone to go!

Treasure: Elegant Headdress (10,000₧)
In the throne room, take a seat. You've earned a rest. But once you're done, look up a little bit to see the Elegant Headdress hanging on a beam above.

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Yellow Herb #21
Passing through the large doors next to the Merchant, you should see the next Yellow Herb directly ahead of you through a broken chain fence.

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Yellow Herb #22
When you're done dealing with everything underground, you'll climb a ladder back outside. Take out the enemies around the campsite, then before climbing down a different ladder, check the area by the cliff for a Yellow Herb.

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Treasure: Blue Stone of Treason (Combinable)
Climbing down the other ladder in the campsite, take a right in the cave and pick up the Blue Stone of Treason. Combine it with the Golden Lynx, and assuming you picked up the Red and Green stones earlier, it should now be complete, meaning you can sell it for 35,000₧.

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The Merchant's final shooting range is also in this cave. There aren't any new games for you, but if you haven't completed the others yet, this is your last opportunity.
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Yellow Herb #23
Once you've collected the first of three insignias, you'll have to climb a staircase in tower to reach the next two. But before going up, you can grab another Yellow Herb at the bottom of the staircase.

Yellow Herb #24
As you make your way through the fort, look out for a breakable barrel next to a fence. It should be just after you kick down a metal door. The barrel contains a Yellow Herb.

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Pearl Pendant (10,000₧)
After the pass through the fort and the ruins on the cliffside, you'll jump down a hole with a ladder. Before passing through the door ahead of you, turn around and pick up the final treasure, the Pearl Pendant.

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Yellow Herb #25
Before going down the hallway with the jail cells, check the side room to the right to find a Yellow Herb sitting on a chair.

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Yellow Herb #26
In the area with the big fight in the outside passage, you can find another Yellow Herb in a locker in the upper Southwest room.

Yellow Herb #27
The final Yellow Herb can be found just as you're leaving the old operating theatre.


The next room contains the Merchant's final shop, so you should sell any remaining treasures you have. If you're playing on Normal or Professional difficulty and have collected all the Yellow Herbs, you should have two left over (or more, if you've decided not to use some). If you want to sell these, try to mix them with a Green and Red herb to get the most money for them.

You might also want to try and leave some space free in your inventory for the upcoming area. You'll get a special weapon in the final battle that will make it easier, but if you decide not to use it, you can sell it in New Game+ for 15,000₧.

Speaking of New Game+, once you've finished the game, make sure to upload your data to the leaderboards, as the "Save Cleared Game" prompt may not show up if you don't.

Congratulations on making it this far, and good luck on the final boss!

Assignment Ada is a short non-canon gamemode, and doesn't include the Merchant and therefore no treasures to sell. There will be white stars on the map, though these are simply your mission objective, rather than treasures. This game mode does however have 7 yellow herbs to find.
Unlike in the main game, each new chapter usually marks a point of no return, so make sure to get everything you want before completing a chapter.

Note that despite coming after Separate Ways in the Extras menu, it's probably best to play it first, as it came out with the original Gamecube release, whereas Separate Ways came out with later releases. Completing Assignment Ada will make the Merchant sell the powerful Chicago Typewriter weapon in Separate Ways for 300,000₧, and completing Separate Ways will make him sell it in the main game for 1,000,000₧.

Additionally, neither this nor Separate Ways are in the Quest VR version. If you're playing that, any rewards you'd normally get from completing them can instead be unlocked from the Mercenaries game mode.
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Yellow Herb #1
Almost immediately after starting, you'll be met with a fork in the road. Take the left path and climb the rocks to find the first Yellow Herb in a breakable box.

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Yellow Herb #2
You'll find the next Yellow Herb in the room where the Chaingunner appeared from, behind the sandbags.

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Yellow Herb #3
In the cave where you found the Golden Lynx statue in Chapter 5-1 of the main game, you'll find another Yellow Herb. It won't be in the same room as the Golden Lynx, instead take the right path as you enter the cave.

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Yellow Herb #4
In the room where you first encountered a Regenerador as Leon, break open the glass cabinet to get the Yellow Herb.

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Yellow Herb #5
Outside the room where Ashley was held prisoner in the main game, the next Yellow Herb will be sitting in the corner.

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Yellow Herb #6
After encountering a bunch of enemies, there will be a small room at the end of the hallway before you enter the Culture Room. It holds the next Yellow Herb along with some ammo.

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Yellow Herb #7
The final Yellow Herb will be at the back of the Culture Room, along with a green and red herb, useful for a full heal!

Separate Ways is a bonus story that can be played after completing the main game, focusing on Ada Wong. If you haven't already, check out Assignment Ada in the extras menu, which (while non-canon), was released first. Completing Assignment Ada will make the Merchant sell the powerful Chicago Typewriter weapon in Separate Ways for 300,000₧, and completing Separate Ways will make him sell it in the main game for 1,000,000₧.
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Treasure: Elegant Mask (Combinable)
Go to the house in the Southeast of the village. Inside, you'll find another door with a padlock. Shoot it off to enter the room and find the Elegant Mask. Don't sell this yet, as you'll be able to find other items to combine it with soon.

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Yellow Herb #1
The first Yellow Herb is in the same position it was in the main story. In the Southwest in a breakable box behind the cow stable. A Red Herb will be nearby, which can be combined with it. Keep in mind that Yellow Herbs have to be combined in order to be used. They can be combined with a Green Herb to increase your maximum health and heal you a little bit, or combined with both a Green and a Red to increase your maximum health (the same amount) and fully heal you.


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Treasure: Green Gem (Combinable)
After meeting the Merchant for the first time, and head down into the cave towards the church. In the wide area of the cave, break the wooden crate with your knife to obtain the Green Gem. You can combine this with the Elegant Mask, but again, don't sell it yet, as there are two more gems to be added to it.
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Yellow Herb #2
In the wooden shack to the West, there will be a Yellow Herb in one of the breakable wooden crates.

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Treasure: Red Gem (Combinable)
You'll find the Red Gem on one of the gravestones in the middle of the area.

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Treasure: Purple Gem (Combinable)
To your immediate right as you enter the church will be a Purple Gem laying on the ground in the corner. You should now have all three colored gems. Combine them with the Elegant Mask and you can sell it to the Merchant for 20,000₧ when you next see him.

Treasure: Brass Pocket Watch (10,000₧)
Before heading downstairs, turn to your right past the Merchant and go outside. Next to the well is a water basin. Shoot the wooden beam to cover the water, then shoot down the Brass Pocket Watch. If you fail to shoot the beam and let the pocket watch fall into the water, it'll only be worth 1,000₧.

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When you're done, you can go back inside the building and sell all the treasures you found so far to the Merchant. Not exactly a treasure, but in the building you start the chapter in, you can find a Golden Chicken Egg in the oven downstairs, which can be used to fully heal you, or be sold for 3,000₧. You can also kill the chainsaw-wielding villager outside the house for a Ruby that sells for 10,000₧.
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No new treasures here, but a bunch of crates/barrels have respawned, meaning you grab some more items.
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There's another water basin next to the typewriter. This one has a Spinel hanging above it. Remember to shoot the wooden beam before collecting it!
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Treasure: Gold Bangle (8,500₧)
Climb the ladder inside the big white barn and then jump out the window. Immediately ahead of you, you're able to jump down into an enclosed area with a breakable crate containing the Gold Bangle.

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Treasure: Beerstein (Combinable)
As you enter, you should see a rope bridge nearby with two villagers on it. Walk under the bridge, then turn around to make the option to use your Hookshot appear. Grappling up to the bridge, you can break a barrel to find the Beerstein. This can be combined with some gems you'll find soon.

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Treasure: Green Catseye (Combinable)
After some backtracking and a bunch of cutscenes, Ada will be in a new location entirely. Once you've taken out the enemies surrounding you, turn around to see a treasure chest with a Green Catseye inside. This can be combined with the Beerstein you found earlier.

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Yellow Herb #3
In the room at the top of the stairs where you find the Merchant, check one of the lockers to get another Yellow Herb.

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Treasure: Red Catseye (Combinable)
Yellow Herb #4
Both of these are in the same place. Before entering the Slaughterhouse, go to the right side of it (where Leon would escape in the main game) to find the Yellow Herb and the Red Catseye.

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Treasure: Yellow Catseye (Combinable)
Partway through the road you can turn around to face some barrels on a ledge. Use your hookshot to grapple up to them and you'll find a Yellow Catseye inside. Now that you have all three Catseyes, combine them with the Beerstein to be able to sell it for 20,000₧.

Yellow Herb #5
The Yellow Herb is found in the same spot as in Leon's story, in the Southwest corner of the maze.

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Treasure: Gold Bangle w/Pearls (10,000₧)
In the middle of the maze where Leon found one half of the Blue Moonstone in the main game, he seemed to have dropped his Gold Bangle with Pearls. His loss is your gain!

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Treasure: Elegant Perfume Bottle (10,000₧)
Once you leave the garden maze, walk into the bedroom and shoot down the Elegant Perfume Bottle from the ceiling above the bed.

Now, instead of progressing through the castle through the bedroom, go back outside and follow the balcony to the door to the Western Castle Wall.⠀
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Yellow Herb #6
Next to the fountain at the Western Castle Wall, you'll see a door next to a big open window. Interact with the door, then you'll be able to use your hookshot to grapple up to the window. Inside you'll find a Yellow Herb, and another item needed to progress the story.

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Treasure: Elegant Chessboard (13,000₧)
When you see Leon in the room that had the free Rocket Launcher in the main game, jump down and look behind the final pillar to the Southeast to find an Elegant Chessboard.

Yellow Herb #7
Near the start of the chapter, you'll see a the path (that includes a Golden Lynx treasure) blocked by an ruined truck and debris. Take the door to your left to get around it, then once back in the tunnel, turn back to face the truck. You'll be able to Hookshot up to the pipe above. Follow this pipe into a vent and you'll find the Yellow Herb.

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Treasure: Golden Lynx (Combinable)
Exit the room where you found the Yellow Herb and you'll see the Golden Lynx in front of you. Once again, there are three stones you need to find and combine with it in order to get the highest selling price.

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Treasure: Green Stone of Judgement (Combinable)
In the room after you deal with the turrets on the battleships, jump down to the lowest floor until you reach a catwalk you need to Hookshot onto. Climb the ladder on the catwalk and look to your right to find the Green Stone of Judgement that can be combined with the Golden Lynx.

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Yellow Herb #8
Continue through the room until you reach a tiny ledge you've got to jump down. It'll be by the locked door you have passed earlier. The Yellow Herb is directly ahead of you.

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Treasure: Red Stone of Faith (Combinable)
After crashing through the skylight into the room with an altar and a typewriter, head North through the double doors before proceeding the normal route. You'll find the Red Stone of Faith in a metal case.

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Yellow Herb #9
Continue into the East room from there and you'll find the Bulldozer that was wrecked by Leon and Ashley. You'll find the Yellow Herb on a shelf in the corner.

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Treasure: Blue Stone of Treason (Combinable)
Go back to the room with the Typewriter and head through the door. Turning to your left you'll see windows by the ceiling. Shoot them to make them drop the Blue Stone of Treason.
Now that you have all three stones you can combine them with the Golden Lynx and sell it for 35,000₧.

Most doors in this chapter will be a point of no return. The first area even has two points of no return within a single load zone, so make sure to grab everything as it appears.

Treasure: Blue Eye (Combinable)
On the building where the chaingunner jumps down near the beginning of the chapter, use your Hookshot to get up to the roof and interact with the flaming barrel to get the Blue Eye. This will be combined with a later item.

I totally didn't forget to pick it up after taking these screenshots
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Yellow Herb #10
This one is hard to miss. It's just before the bridge, sitting by the sandbags.

After crossing the bridge into the building, you won't be able to obtain these two items anymore.
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Yellow Herb #11
After being trapped in the room with a bunch of enemies, drop down to the lowest area with the tents and check the small mineshaft for another Yellow Herb.

Once you raise the shutter and go through, you will no longer be able to obtain this, so get it now.
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Yellow Herb #12
In the area with the enemy that had a rocket launcher, break the barrel inside the collapsed ruins in the middle to find a Yellow Herb.

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Treasure: Red Eye (Combinable)
Close to the Yellow Herb, shoot the shining spot on top of one of the pillars to get the Red Gem. You can't combine this yet, but hang onto it!

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Yellow Herb #13
Just like in the main game, before going down the hallway with the jail cells, check the side room to the right to find a Yellow Herb sitting on a chair. This is the final Yellow Herb in the game.

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Treasure: Green Eye (Combinable)
In the corner of the second jail cell on the right will be the Green Gem. If you had a Butterfly Lamp you'd be able to combine all these gems, but you'll have to wait a little longer for that.

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Immediately after the boss fight, Ada will hookshot over to another building. Turn to the left and round the corner as you land to find the Butterfly Lamp. You can combine this with the colored Eye Gems you found to sell it for 32,000₧.

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Note about New Round for Separate Ways:
For some reason, players occasionally aren't taken to the save screen when prompted to save after the end of the game. If this bug happens to you, you'll unfortunately have to load your last checkpoint/save and fight the final boss again. Players have reported that it'll usually let them save the second time.
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