Overview
Brain of Cthulhu is a boss in Terraria, rendered as a composite of 6 NPC segments. This guide pulls together the official spawn rules, drop table, and progression context so you can decide when to attempt the fight and what to bring.
How to summon
Bloody Spine, or break 3 Crimson Hearts.
Notable drops
- Brain of Cthulhu Trophy (1 in 10)
Fight composition
Brain of Cthulhu is composed of 6 pieces (Brain of Cthulhu, Creeper, Creeper, Creeper, Creeper, Creeper). Plan your weapon choice around hitting all parts — piercing weapons or wide AoE tend to outperform single-target damage.