Just Desserts 
Instant
Just Desserts deals π damage to target creature. (π is the ratio of a circle's circumference to its diameter. (It's a smidgen more than 3.))
Legality
standardNOT LEGALpioneerNOT LEGALmodernNOT LEGALlegacyNOT LEGALvintageNOT LEGALcommanderNOT LEGAL