This guide is a translation of another guide, also made by me. English is not my main language, so there may be some typos. Please, don't be so harsh about it.

Bonfire Ascetics are a rare, valuable, and useful item.
Their only use is to burn them on a bonfire, doing so will strengthen the enemies of the area, making it NG+, this means that the enemies will have more HP, and will deal more damage, but this also means that some unique items, enemies, or even bosses, will respawn.

There are some unique enemies with valuable drops that, most of the time, do not respawn unless we burn an ascetic on a bonfire nearby. Also, burning a bonfire ascetic near a boss will respawn the boss, this will allow you to fight the boss again and get another one of it's boss souls.

Burning a bonfire ascetic, as the game itself says, is something that cannot be undone, so think twice before you do so, or else you may not be able to progress through the area you burned the ascetic in.

• 1 Branch of Yore
• Must have already beaten the "Guardian Dragon" boss.
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• First, we'll head up to the first bonfire of the area. This is the bonfire we'll be using during the farming process.

• Now, we'll head up into Aldia's keep...

• ... And as soon as we step inside, we'll be invaded by the NPC "Aslatiel of Mirrah", Lucatiel's brother. This NPC invader is the only real enemy we'll find during this farming process. It's not a hard-to-beat NPC, so It won't take you long to vanquish him.

• Once we're done with the invader, we'll head up into the Aldia's Keep principal chamber, the one with the giant dragon skeleton.

• We'll ignore everything, and will go straight up the stairs on our left. Once up, we'll find a Giant Basilisk on a cage, It won't attack us unless we do attack it, or come too close.

• We'll walk a little close to the cage, and we'll focus on the petrified hollows nearby, we'll need the one that's closer to the staircase for the farming.

• We'll proceed to use the Branch of Yore on it, that'll unpetrify it.

• We'll finish him off and we'll grab his drops, 2 Bonfire Ascetics. This hollow will not respawn until the next NG cycle.
(Note: The text on the image is on spanish, but I can assure you It means "Bonfire Ascetic x 2")

• And, In order to make the area a higuer NG level, we'll have to burn one of the bonfire ascetics we got. We'll go back to the first bonfire of the area, and we'll do so. The game will not allow us to burn an ascetic unless the "Guardian Dragon" boss is dead. However, once we burn an ascetic on this bonfire, the boss will not respawn.

• Now that we've burned one of the ascetics, we'll head back inside Aldia's keep. Inside, we'll once again be invaded by Aslatiel of Mirrah.

• Once we finish him off... or run past him, we'll once again go up the stairs on the left, and we'll search for the hollow, it'll be unpetrified, and will probably attack us on sight, so it won't be hard to find.

• We'll finish it off, and again, It'll drop 2 Bonfire Ascetics.
We can repeat this process as much times as we want, and each time we do so we'll get 
1 Bonfire Ascetic. In my opinion, this is the safest, easiest, and quickest method if you want to farm bonfire ascetics.
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• Each time we burn an ascetic on the first bonfire of Aldia's Keep, Aslatiel of Mirrah will invade us. This will allow us to farm a few Souls and Human effigies from him. We can also farm him for his unique drop, the "Old Mirrah Greatsword", which has a very low drop chance.

• Also, if we're in the "Company of Champions" covenant, we can use Aslatiel to farm Awestones instead of Human effigies. However, being in the Company of Champions covenant will make Aslatiel deal more damage, making the fight a little harder. There are also better and quicker ways to farm awestones.
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• If we have an extra Branch of Yore, we can unpetrify the other Hollow nearby.

• This one hollow will drop us 2 Elizabeth Mushrooms & 2 Wilted Dusk Herbs, those are some rare items that are pretty useful, really.
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• This is the first guide I make, so please, tell me what you think. Also, thanks for reading it!
• That'll be all, take care, dudes! ~ James Hermit, the Iron Turtle