Brainy Zombies are a new threat introduced by Thaumcraft. They are the only source of Zombie Brains, and a secondary source of Distorted Skulls and Rotten Flesh. They heavily resemble vanilla zombies, but are distinguished by their bulgy-looking forehead, red eyes, and boosted health. They spawn in packs of 1-3, in all vanilla biomes. they can also open doors instead of breaking them down. This does not only happen on hard, but also normal diffculty.