I got some ideas for executions.
Whitty:(Off with a bang) Monokuma will ignite the fuze on his head, Whitty will try to put it out, but he can't. The execution ends with Whitty's head exploding.
Hex: (Computer crash) Monokuma (dressed as a cat) will jump on Hex, and kick a huge glass of water on him. This will cause Hex to malfunction, but no one can do anything about it. The, Hex will eventually shut down.
Kapi: (Fancy Footwork): Kapi will appear in a room, his dance pad is there, but instead of touching the glowing arrows, he needs to avoid the glowing arrows. Because blades will pop out in front, to the right, to the left, or behind Kapi. It gradually goes faster, making Kapi tired out. Near the end, when Kapi thinks its done, one last blade pops out and cuts Kapi's feet off. At the end of the execution, you can see a screen that says "game over" and right in between the screen and his dance pad, lies a lifeless Kapi. With a tremendous amount of blood coming out of his legs.
(I know Pom Pom's not on here, but let's do her anyway)
Pom Pom: (Deadly as Pie) Monokuma will push Pom Pom into a pie, shaped cell. The "pie" will slowly be moved towards a giant oven. The heat will rise gradually. Burning Pom Pom, and the pie. When the execution is done, all that will be left of Pom Pom will be ashes and bones
