Mr. Bun Bun is the main antagonist in Underfist: Halloween Bash.
Bun-Bun is a marshmallow bunny that tried to rule the world but failed because of Underfist. He did several things that really hurt some of the characters. These are:
- Haunting Hoss when he was young and made him hate all monsters.
- Putting a witch worm in Mindy's hair turning her into a witch.
- Making Billy afraid of spiders so he would not love Jeff.
- Sawing off Fred Fredburger's tusks (he didn't seem to care)
It's unknown why he scared Hoss, made Billy afraid of spiders and sawed Fred's tusks off. The most possible reason that he was actually an underworld monster resembling a rabbit.
He later recruited Skarr to help him rule the world but Skarr betrayed him and kicked him in pot of hot cocoa and he melted to his death. Before disappearing, he took the form of a vapor and angrily yells out "What did I ever do to you guys?" and vanishes.
Background
Much of his background is unknown but he did mention that the other marshmallow bunnies called him soft. He seems to be an crazed egomaniac.