- 弱效治疗药水 (5-15)100%
- 内部 NPC ID: 266
克苏鲁之脑有两个阶段，一开始，大脑是无敌的，并且会在玩家周围随机传送。 会有 20 个飞眼怪伴随 Boss 生成，绕着它高速飞行。飞眼怪被击杀后不会重生。先要击杀所有的飞眼怪，随后克苏鲁之脑才会进入第二阶段，此时它才有弱点可供攻击并击杀。
当the Brain of Cthulhu活着时，会播放《Boss 3》音乐。
- 在专家模式中，克苏鲁之脑会得到70% 生命值提升。这会将其在经典模式中的 1000 生命值提升至 1700。
- In Expert mode, the second phase now has three mirror images of the Brain appear around the player, mirroring the Brain's movements and becoming more opaque as the boss loses health.
- Furthermore, both the Creepers (in the first phase) and the Brain (in the second phase) inflict a random debuff upon contact. The probabilities of applying each debuff are listed in the following table; note that the Creepers always inflict a debuff while the Brain only has a
33.33*1/3 (33.33%) chance to do so. Debuff Duration  Chance (Brain) Chance (Creepers) 专家模式 大师模式 中毒 5.25 - 10.5 seconds 6.56 - 13.13 seconds 4.53*11/243 (4.53%) 13.58*11/81 (13.58%) 黑暗 3 - 6 seconds 3.75 - 7.5 seconds 4.53*11/243 (4.53%) 13.58*11/81 (13.58%) 被诅咒 0.75 - 1.5 seconds 0.94 - 1.88 seconds 0.82*2/243 (0.82%) 2.47*2/81 (2.47%) 流血 7.5 - 15 seconds 9.38 - 18.75 seconds 4.53*11/243 (4.53%) 13.58*11/81 (13.58%) 困惑 1.5 - 3 seconds 1.88 - 3.75 seconds 0.82*2/243 (0.82%) 2.47*2/81 (2.47%) 缓慢 5.25 - 10.5 seconds 6.56 - 13.13 seconds 4.53*11/243 (4.53%) 13.58*11/81 (13.58%) 软弱 11.25 - 22.5 seconds 14.06 - 28.13 seconds 4.53*11/243 (4.53%) 13.58*11/81 (13.58%) 寂静 1.5 - 3 seconds 1.88 - 3.75 seconds 4.53*11/243 (4.53%) 13.58*11/81 (13.58%) 破损盔甲 9.75 - 19.5 seconds 12.19 - 24.38 seconds 4.53*11/243 (4.53%) 13.58*11/81 (13.58%)
- All Expert mode changes apply.
- In Master Mode, the Brain of Cthulhu gains a 27.47% health increase. This brings its original Expert Mode health of 1700 health up to 2167 health.
- The debuffs inflicted by the Brain and the Creepers are extended in duration, as detailed in the table above.
- Creepers are more aggressive in 专家模式 and 大师模式.
- Two Brains can be summoned at once by smashing Crimson Hearts. They seem to share their Creepers and go into their second phases simultaneously.
- Note that actually defeating the Brain of Cthulhu is not completely necessary to progress, as the Creepers may drop the needed amount of materials.
- Crafting the Deathbringer Pickaxe (from Tissue Samples and Crimtane Ore) will not be necessary if the player obtains the Reaver Shark (through fishing).
- Creepers have low individual health and are especially susceptible to the On Fire! and Frostburn debuffs. Weapons that inflict these debuffs can make quick work of them.
- Grenades and other splash damage weapons can kill the Creepers very quickly, as they will bunch up often.
- Since the Brain of Cthulhu is susceptible to knockback, weapons with high knockback such as the The Rotted Fork can keep both Creepers and the Brain from closing distance between teleports. It is also possible to use early-game melee weapons such as the Katana or the Zombie Arm as long as they do not have disadvantageous modifiers. It is preferable to use spears for this fight since they deal more knockback, however, so the Trident or The Rotted Fork is recommended.
- Note that this may not work in 专家模式, since it might be hard to tell which Brain to attack among the illusions.
- Jester's Arrows or other enemy-piercing weapons can be immensely helpful while fighting the first stage, since Creepers often group up in a clustered formation, effectively allowing the player to hit most if not all of the Creepers in one well-aimed shot.
The Quad-Barrel Shotgun is an excellent weapon to use for the brain's second form. It deals extremely high close-range damage and can end the fight before the Brain’s illusions get too opaque.
- There are several methods to reveal the real Brain of Cthulhu in the second stage:
- A Hunter Potion will only highlight the real Brain.
- The real Brain is the only one with a health bar.
- The illusions position themselves in relation to the player. The illusions will quickly spread away from the real Brain if the player is walking away from it, but the real Brain will continue to move at a steady pace.
- The minimap displays only the real Brain.
- 克苏鲁之脑，以及多个其他 Boss，都是基于克苏鲁的，它是霍华德·菲利普斯·洛夫克拉夫特（H. P. Lovecraft）在他的短篇小说《Cthulhu 的召唤（The Call of Cthulhu）》中第一次想象出来的生物。
- The Brain of Cthulhu has the least health out of all the bosses, with even less than the Eye of Cthulhu in its second form. However, when adding in the health of the Creepers, it has more health than King Slime.
- 克苏鲁之脑是唯一受击退作用的 Boss。
- 与流行的看法相反，飞眼怪并不会掉落暗影之魂、 生物群落钥匙、或 生物群落钥匙模具。
- It is one of the only three bosses whose map icon does not change after entering its second phase, the others being Santa-NK1, and Queen Slime.
- The Brain of Cthulhu is sometimes abbreviated as "BoC."
- The list of debuffs inflicted by the Brain and Creepers in Expert Mode just so happens to be exactly the same as the list of debuff immunities granted by the Ankh Charm. The Ankh Shield also gives these immunities, with the addition of Burning and Chilled. Of course, it is fairly trivial to defeat the Brain of Cthulhu at the point in the game that the Ankh Charm can be obtained.
- On the 电脑版, a cloud in the shape of the Brain of Cthulhu can occasionally be seen in the background.
- 克苏鲁之脑的 怪物图鉴条目：“A piece of Cthulhu torn asunder, this vile mastermind pulses with agony and aids the Crimson to an attempt to avenge its master.”
- 电脑版 220.127.116.11：外观更新。
- 电脑版 18.104.22.168：Defeating the Brain of Cthulhu now allows Meteorites to fall rather than breaking a Crimson Heart, and defeating more Brain of Cthulhus will increase the chance of a Meteorite falling the following night.
- 电脑版 22.214.171.124：
- 电脑版 1.2：引入。
- 主机版 1.02：引入。
- 移动版 1.2.6508：引入。
- 信息来自 电脑版 126.96.36.199 源代码，
- 信息来自 电脑版 188.8.131.52 源代码，
aiStyle == 54下面）；以及
- 信息来自 电脑版 184.108.40.206 源代码，methods