mono black armageddon advantage

Each land is a Swamp in addition to its other land types.

Target opponent sacrifices a creature of their choice for each creature put into your graveyard from the battlefield this turn.

All Swamps are 1/1 black creatures that are still lands.

Each player exiles all creature cards from their graveyard, then sacrifices all creatures they control, then puts all cards they exiled this way onto the battlefield.