During Cosplay chess, I (cosplaying the legendary pokemon Jirachi) was a summon for the Ash Ketchum cosplayer (on the anime side of the board). He summoned me, I did a Hyper Beam, and that was the last time he summoned me...
Because the next person that summoned me Yuna. (on the video games side of the board)
And she summoned me, TO KILL ASH KETCHUM!
it basically went like this:
Me: you want to know why I've switched sides, Ash? Because I'll tell you why. YOU, Ash Ketchum, are an annoying, pathetic excuse for a Pokemon trainer who can't train his Pokemon for squat. You irritate me, you disgust me, you waste my time, abilities, and patience. I'm not going to take it anymore, so you can take that master ball and shove it!
Then I (pretend!) slapped him. He died by his own Pokemon, it was as though someone planned it!
I eventually learned that the audience couldn't make out what I had said, though. It sounded like shrieking.