Harsh Mercy 
Sorcery
Each player chooses a creature type. Destroy all creatures that aren't of a type chosen this way. They can't be regenerated.
Legality
standardNOT LEGALpioneerNOT LEGALmodernNOT LEGALlegacyLEGALvintageLEGALcommanderLEGAL
Sorcery
Each player chooses a creature type. Destroy all creatures that aren't of a type chosen this way. They can't be regenerated.