The Brain Twins

The Brain Twins are the war mode version of the Brain of Cthulhu. They're spawned with the All-Seeing Brain. They are looking like an blue scaled and a red scaled brain. They can be spawned everywhere, but it has to be night and war mode. The Freezer is the icy brain, while the Infernal is the fire brain.

Stats

 * The Freezer: 100000 HP (120000 HP in Expert)
 * The Infernal: 100000 HP (120000 HP in Expert)
 * 100 damage (both) (150 in Expert)
 * 50 defense (both) (75 in Expert)
 * 70 damage (Fire Rain) (80 in Expert)
 * 90 damage (Infernal Wave) (100 in Expert)
 * 80 damage (Freezing Tentacle) (90 in Expert)
 * 80 damage (Icy Beam) (100 in Expert)

Stage 1
They will flight to you. The Infernal shoots his fire rain, while the Freezer tries to hit you with his Freezing Tentacle. The Fire Rain can inflict Inferno, while the Tentacle can inflict Frozen. After both made their attacks 2 times, they will charge at you.

Stage 2
The Freezer and the Infernal will both get an Shield. They are now invincible. They will spawn 20 Melted Creepers, which have 500 HP and will charge at you. Kill them, and you get in the Final Stage.

Final Stage
After defeating the Creepers, the Brains Shield is gone. Freezer will shoot Icy Beams, while the Infernal will shoot Infernal Waves. They will charge at you, then shoot three of their attack, then charge again, repeating the process. If one of both haves 0 HP, it will get almost invisible and will follow the other brain. That means if Infernal is killed, it will follow Freezer and vice-versa. When both are at 0 HP, they will collide, leaving water at their collide point. You defeated them. The drops will be in the water. When defeated, Freezed Ore and Infernal Ore will spawn at the Underground Snow Biome and in the Hell.

Drops

 * 10-20 Frozen Bars
 * 10-20 Infernal Bars
 * 1 Platinum Coin
 * 10-20 Super Healing Potions
 * Treasure Bag (The Brain Twins) (will contain the drops above, as well Fire and Ice.)