Thumper

Thumpers are immobile Skull-based enemies in the same family as Hosts. When lowered down, which is their normal state, they are invulnerable and immune to explosions. Occasionally, they will briefly pop up and reveal a fleshy stem that can be damaged. When this window ends, they slam down and release a chaotic splash of red shots in all directions, returning to their lowered state.

Like their vanilla parallels, taking a large amount of damage at once while lowered will cause them to grimace. Grimacing prevents them from firing any shots until they return to normal.