Upon triggering, one character at random is teleported to a cage in a hidden room nearby, while a beast of the GM's choice (consult your favorite monster tome) is teleported from this cage, to the exact spot where the character had been standing. From the players' points-of-view, it will appear as though the affected character has been polymorphed into the beast! This gag can be enhanced if the GM has the player of the teleported character actually roll the dice and fight as the beast. The beast attacks the party immediately. Other characters may well be conflicted about killing their own party member (as they see it). After the fight has died down, the GM may then announce that they can hear a voice coming from a hidden panel, behind which is the missing character. Optional: The party can't hear the character calling for help; it will be up to them to get out on their own.
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