Mister Stabby is a Hardmode enemy that only spawns during the Frost Legion event. It chases the player through most terrain that it was encountered, and occasionally stops to do a considerably long stabbing animation with his knife. When attacking the player, he will dash and bounce around the terrain, making it difficult to hit him. Arguably, the best way to combat its speed and rapid bouncing is to use a spear or a decent ranged weapon.
Mister Stabby is immune to the Poisoned, On Fire!, Venom, Shadowflame, and Cursed Inferno debuffs.
- Mister Stabby is the only snowman from the Frost Legion that does not have a visible smile on its face.
- He appears to be holding his knife by the blade, instead of the handle.
- Mister Stabby may be a reference to the flash animation series "Mr. Stabby", by Weebl's Stuff.