I'm gonna nominate Kaboom! ! It's a great card for multiplayer and always chancy unless you manipulate your library somehow. And it's got an excalmation point in the card name! 
Final nominees:
Goblin Sharpshooter - orgg
Future Sight - Oversoul
Biorhythm - DarthFerret
Grand Melee - Ransac
Kaboom! - Spiderman
Closed for voting.
Final nominees:
Goblin Sharpshooter - orgg
Future Sight - Oversoul
Biorhythm - DarthFerret
Grand Melee - Ransac
Kaboom! - Spiderman
Closed for voting.