The Mad Doctor is one of the Lesser Sons that can spawn near the Fortresses as miniboss. Created by Kacperlupa.polska.


The Mad Doctor is a bigger Injector, but he also has two barrels on sides of lance. His liquid constantly changes colors.


  • Injection: He quickly charges at the tank and gives it Slowed, Poisoned or Blinded for 5 seconds.
  • Pills of Doom: Shoots out ovular bullets that deal big damage despite being, well, not quite big.
  • Medicine: He gives himself Hasty or Strength for 20 seconds. Has a 1% chance of gaining Invulnerable.
  • Unstable Substance: He shoots out color-changing bullet that explodes after 1-3 seconds or contact with anything.
  • Ex-treme Ex-tending: Pushes his back part while extending his lance to twice the original length. Simple yet effective.
  • Experiment #538: Spawns a big durable green minion that changes its type every 5 seconds. Can be:
    • Smasher with two Battleship spawners,
    • Twin Flank with one barrel instated of two on one side,
    • Hunter with trap launcher on back.


  • Yes, that number of experiment was random.
Community content is available under CC-BY-SA unless otherwise noted.