Carrion Rats

Whenever this creature attacks or blocks, any player may exile a card from their graveyard. If a player does, this creature assigns no combat damage this turn.

Chittering Rats

When this creature enters, target opponent puts a card from their hand on top of their library.

Rats' Feast

Exile X target cards from a single graveyard.

Swamp

Crippling Fatigue

Target creature gets -2/-2 until end of turn.
Flashback—{1}{B}, Pay 3 life. (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Dirty Wererat

{B}, Discard a card: Regenerate this creature.
Threshold — As long as there are seven or more cards in your graveyard, this creature gets +2/+2 and can't block.

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