Annihilation

[MunchkinMan]

You have to resolve your Run Away attempt. Annihilating a Monster that has already caught you is not a legal way to get out of the Monster's Bad Stuff. Playing Annihilation on the Monster before you roll, sacrificing a Hireling (found in Munchkin 4 and 5), or using the Wizard's ability to discard some cards to bump your roll (before the roll if using previous printings' Wizard, after if you're using the 19th printing Wizard), or playing a Magic Lamp are the most likely ways you're going to do that in the original game.