First of all Wild Mages: Wild Mages basically cast spells more powerfully, but the magic they wield has unpredictable effects sometimes called a "wild magic surge".
In the coming story, the wild mage is Chaotic Neutral, and is secretly working for the bad guy.
The party were coming up against the big bad of the campaign, a scheming wizard who had taken control of most of the country. Player A, the wild mage was, as befitting a wild mage, chaotic neutral, and befitting a player who had confused chaotic neutral with jerk, he was about to screw the party over.
For the upcoming battle he had informed the big bad of their plans, and had convinced the party that he had a foolproof plan, that he would cast a spell specifically designed by the resistance in the country that would kill the big bad (long story.) Anyway, the betrayal comes in the final battle.
Player A passes note to DM: "I cast invisibility spell on the enemy instead"
Player A: NOW! See what happens to my enemies! (Casts spell)
(Predictably) Wild Surge (DM: *Giggle* Player A: Oh...)
Result: Roll 4 more times, all effects apply (DM: Teehee. Player A: Uh Oh....)
Results: Music plays in background, Target sex changes, All cloth on target turns to dust, Target knocked unconscious. (DM: Muahaha! Player A: Gah!)
Spell Cast! Result: Big Bad now an unconscious naked female. With some romantic music playing in the background.
Party: ... this is so wrong ...
All credit for this story goes to "Heads_or_Tails" on the Giant in the Playground forums.
