[TCB_WyattEarp]

I wonder if this could be done by incorporating the monster mod which I had on my server at one time for the bad_camper plugin, not sure but maybe rather than a hostie dealing the deed, you could spawn a monster kill the offending player and then disappear. ?

OR
Rather than pull a pistol and kill the player, the hostage model could just slap the player for 100 damage.