Bun Bun Black (ブラックブンブン, Hepburn: Burakkubunbun, literally Black Bun Bun) is a Black/Floating enemy that only appears in Stories of Legend and various event stages.
The Black/Floating variant of Teacher Bun Bun who is bigger.
Since his damage output and movement speed are both 2/3 of that of the original 400% Teacher Bun Bun encountered in Moon, in addition to having a second trait, Bun Bun Black is actually less threatening than Teacher Bun Bun under most circumstances.
The True form of Shaman Cat works effectively against this enemy and all of the alternate forms (excluding Relic Bun).