
If an opponent controls a Plains and you control a Swamp, you may cast this spell without paying its mana cost.
All creatures get -2/-2 until end of turn.
Massacre has 4 printings, first in Nemesis (2000). EDHREC ranks it #11,761 among Commander cards. It appears most in Massacre Girl, Known Killer decks (1,157 on EDHREC). 1 public deck on TCG runs it.
Deck counts from EDHREC.
Cards that show up in the same decks on EDHREC.