The Impossible King Slime is a pre-impossible boss.

He is a MASSIVE slime, roughly 25x bigger than the Rainbow Slime

Impossible King Slime can spawn under one of the following conditions:

  • A player uses an Impossible Slime Crown
  • 22,500 Slimes are defeated in the slime rain/5,625 if he has been already defeated.
  • Rarely in the outer thirty sixths of the map, during daytime and only on grass.