For the fight, iron armor and a shackle is enough for armor. 160 health is enough for the fight, but 180 is fine. For arrows, 500 flaming arrows is enough. Ironskin and Swiftness Potions are recommended. 5 Lesser Healing potions is plenty. This should be your hotbar: 1.Iron Broadsword (or better) 2. Iron Bow (or better) 3. Lesser Healing Potions, and that's all you need. For buff potions, press 'b' when you see the Eye getting close to you, so you get the most of your potions. A stadium is necessary, this is how I made mine: 1. Dig a 27 long, 1 deep hole and replace it with wood 2. Stack up 31 pieces of wood from the edge of both sides, and cover up the roof 3. Place a layer of wooden platforms for every 5th layer until you have 5 layers of platforms. 4. Put torches on the end of each layer 5. Add 1 door to each side. And that's a good stadium for the fight.

At the first part of the fight, the Eye will hover over the stadium, and will only hurt you if you touch it. It will send in a few (3 or 4) Servants of Cthulhu, then charge at you. For the servants, I suggest taking them you with a sword, then shoot the Eye when he's charges into the stadium. After a few arrows, he should retreat and send in more servants. Keep doing this until he is at half health (1400), and he will spin on the spot for a few seconds. At this time, keep shooting him with arrows if you're far away, and hit him with your sword if you're next to him.

After he's done spinning in circles, he'll stop sending Servants of Cthulhu, change into a mouth and will start charging at you constantly. His attack will rise dramatically but his defense will drop. Personally, I think this part is a bit harder. I recommend circling around your arena and spam flaming arrows at him. he should do about 12-18 damage, so don't go at him wiht your sword. With this strategy you should be able to beat the Eye by using about 3 Lesser Healing Potions, but bring 5 in case of any emergency.

After you beat the Eye of Cthulhu, he should drop lots of items and money. The only things you really need are the Demonite Ores, the Unholy Arrows and the Corrupt Seeds. Go to a chest and put away Unholy arrows and Corrupt Seeds (you don't need them yet), and go to a furnace to make Demonite Bars. I recommend making a War Axe of the Night, but it's your choice.

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