Eye of Cthulhu

The Eye of Cthulhu is a bigger version of the Demon Eye and is a boss enemy.

To summon it, you will first need 10 Lenses and be standing near a Demon Altar to craft a Suspicious Looking Eye. The player can use it to summon the Eye of Cthulhu. This boss is thought to be the easiest boss by the game developers.

An often used strategy and probably the best way to kill it is to buy a large number of shuriken from a merchant, despite the fact that it takes a lot more time. (Holding down right mouse button reduces time) Buying 500 of them should be enough to kill it.

The Eye of Cthulhu will occasionally spawn naturally when you have killed 20+ Demon Eyes (though it can happen without the player ever touching a Demon Eye), and is indicated by a status message to the player: "You feel an evil presence watching you..."and later "The Eye of Cthulu has Awakened!" If the message occurs during the day, the Eye of Cthulhu will not spawn until nightfall. Similarly, if a player recieves the presence message while under "Level" (according to the Depth Meter) the Eye will wait until the player has moved above Level to appear. It also seems the Eye will not appear if the height is greater than 300.

If a player attempts to summon during a fight with an Eye Of Cthulhu during the day, they will instantly be slain. The player will also instantly be slain if they try to summon a second Eye of Cthulhu while one is already attacking him/her.

While fighting the Eye, do note that if day breaks, the battle will end and the Eye will run away, forcing you to summon it again. In single player, the player's death marks the end of the boss battle. In multiplayer, if no one is alive for the boss to shift attention to, then the battle is over as well. However, boss will keep on attacking you on following nights until you finally manage to kill it.

If a player uses the Suspicious Looking Eye after he received "You feel an evil presence watching you..." message (provided that he received the message at night) an Eye Of Cthulhu will spawn and shortly after another Eye Of Cthulhu will appear, thus leaving the player to fight two bosses at the same time.



Phase 1
The Eye of Cthulhu can only be summoned at night and will disappear without dropping any loot if the player does not kill it before day.

Although not required, it's recommended to use a ranged weapon to kill it. Melee weapons damage it, but hitting the Eye of Cthulhu is very difficult, as it sometimes flies through walls and terrain, as well as the air.

The Eye of Cthulhu has 3000 HP in both single player and multi-player.

During Phase 1, the Eye of Cthulhu also periodically spawns Servants of Cthulhu.

You also get a small bonus damage when hitting the pupil.

Attack Pattern: He will hover around the player and shoot out a very fast Servant of Cthulhu every second or two, then after four (Sometimes five or even six) have been launched, he will dive towards the player three times and repeat until his FP reaches 1500. -FMD

Phase 2
Once the Eye reaches about 1500 HP, the second phase commences. This doubles the amount of damage it deals and changes the sprite so that it looks like a mouth (replacing the iris and pupil) with a set of large, sharp teeth. The Eye also takes slightly increased damage during this phase.

In the 2nd phase, instead of spawning servants, the Eye will charge at the player 3 times, take a short break and then repeat. It continues this pattern until death or daybreak.

Strategies
One viable strategy is to buy the Flintlock Pistol (after breaking a Shadow Orb and obtaining the Matchlock so that the Arms Dealer NPC will move in), buy around 400-500 (32 Silver-40 Silver) rounds of ammunition, and possibly find the cloud in a bottle or some other accessory that will aid in swift movement/jumping. The cost difference is usualy not bad (You will earn about 3+ gold at the end, after the 32-40 silver) Should you run out of ammunition, it helps to have an Enchanted Boomerang, it is fairly common in chests underground. It does moderate damage, the problem is its speed, and time is something you cannot afford in this fight, so use it as a last resort. -FMD (Thanks to Tipster)

Note: You should have at least found a few Crystal Hearts, and have at least 10 or so Lesser Healing Potions for the occasional screw up. If you cannot afford the ammuntion be careful, as it might take too long to kill him and before you know it daytime will ruin your fight as well as your time/money.

Battlefield
It is possible to just fight the eye on whatever spot you choose, but it is much easier to construct a battlefield before hand. Try to contruct it close to your base (Not so close that NPCs are in danger, but close enough that the NPC's effect of keeping enemies away in a certain radius is intact) and then construct large wooden platforms in a line, preferably two, so that it looks like the screenshot (Attempt to test out the platforms and get a feel for quickly going up and down with the down key so that you can quickly drop down 2 levels if its needed) Try to have many torches around if possible so that when he clips through the ground you can keep track of him. The walls are optional, when I constructed it they were not needed as I was near my base, but if you are not then it is a good idea, otherwise zombies and the like are sure to show up as the fight can only take place at night.

Rewards

 * Gold
 * Crystal Heart (not always)
 * Demonite Ore (not always)
 * Unholy Arrows
 * Coins
 * Small Hearts
 * Corrupt Seeds