My ex did beheaded zombies, imps, and nazis with walking and falling frames. He also did zombies, imps, nazis, demons and cacodemons with a green crossbow bolt buried in them as they die.
There's also some other enemies. The flamethrower marine (I think from Diaz... But I'm really not sure) with a crossbow bolt in his neck, the Hell Rose (that plant monster from Blood) on fire, the rebel from strife with a crossbow bolt in his chest, and uh... I think that's it.
He told me that he didn't care who did what with them, which I guess constitutes permission and/or credit. Want 'em?