Okay, so it's the climax of the plot, and most of the good guys and bad guys are either gone or dead. The hero is stuck in the villain's base/superweapon-to-kill-all-mankind, and he can't find the Big Bad to defeat him. So he decided he's just going to TAKE THE WHOLE BUILDING DOWN, even though he know he'll probably die in the ensuing collapse or (more likely) explosion. Very similar to "Taking You with Me", but with a building or ship or spacecraft or... just some sort of massive thing that spells doom for all. And a badass hero gone berserk, because he isn't willing to let mankind die, dying epicly as he madly hacks and slashes (or shoots a la 'more dakka') destroying until the doomsday weapon is destroyed.