True Eye of Cthulhu

True Eyes of Cthulhu are invincible Hardmode enemies that are summoned by the Moon Lord when you kill the eyes on its head or on one of its hands. Since the Moon Lord has 3 eyes for you to "kill" before his core is revealed, there will always be 3 True Eyes of Cthulhu pursuing the player until the very end of the battle.

Attack

 * The True Eye of Cthulhu will appear after the head or either hand of the Moon Lord has been slain. They will orbit the Moon Lord and pursue the player, generating white balls of energy which they then fling at the player frequently. They also have a miniature beam similar to the Moon Lord's deathray that generates from his head, though the beam generated by the True Eye of Cthulhu is far easier to avoid. They deal up to 50-150 damage to the player.

Tips

 * To prevent overwhelming yourself with the attacks the True Eyes of Cthulhu damage you with, try and "release" all 3 eyes all at the same time. That way, by the time the Moon Lord reveals its core, you won't be as damaged as you would if you "released" the eyes one by one.
 * Using good dodging gear, such as the Master Ninja Gear, can help you avoid its attacks.

Trivia

 * The True Eye of Cthulhu, along with the Spike Ball, Blazing Wheel, and flying Golem Head are the only truly invincible enemies.
 * Although they are called True Eyes of Cthulhu, they spawn when one of the Moon Lord's eyes are defeated. This is because the Moon Lord is based off of the design of Cthulhu.

History
Véritable Œil de Cthulhu 克苏鲁真眼