Exxo Avalon/Oblivion

Oblivion is a  and the final boss in Exxo Avalon.

Spawn
Oblivion does not spawn on its own, and must be summoned with the at Night.

First form
The first phase of Oblivion is similar to the Eye of Cthulhu in appearance. However, it will fire occasional dark matter fireballs at the player(s) in the eye phase. It will also occasionally spawn World Feeders to its aid. When this phase gets to 1/3 HP, it will spin and turn into an eye-mouth, also similar to the Eye of Cthulhu. It will then spew dark matter flamethrowers at the player(s). Instead of World Feeders, it will now spawn Mechanical Diggers instead. Once this phase is dead, it drops to the ground and is undamageable. After 5 seconds, it will switch to its second form.

Second form
"Oblivion has been reborn!"

In its second form, Oblivion is identical to Skeletron Prime, except that there are 2 heads; in addition, the arms will be different. The laser arm will fire a 360 degree spread of lasers, the bomb arm will fire homing bombs that explode on contact with the player, and the other two arms will be like Skeletron Prime's arms.
 * At half health, the purple-eyed head will spawn Astigmatazer and the yellow-eyed head will spawn Infernaspaz.
 * Also at half health, the yellow-eyed head will spawn The Twins and the purple-eyed head will spawn the Destroyer.
 * Once the purple-eyed head reaches 40,000 HP or lower, it will begin to fire a 360 degree spread of bombs from its center.
 * Once the yellow-eyed head reaches 50,000 HP or lower, it will begin to fire a 360 degree spread of lasers from its center.

Trivia

 * Oblivion's "yellow" head has 150,000 HP, which is the same amount as Ultrablivion. This boss was the final boss of the tConfig mod.
 * A special health bar appears in both of Oblivion's forms. This is similar to Ultrablivion's in the tConfig mod.