Disfigure

Target creature gets -2/-2 until end of turn.

Duress

Target opponent reveals their hand. You choose a noncreature, nonland card from it. That player discards that card.

Swamp

Burglar Rat

When this creature enters, each opponent discards a card.

Ravenous Rats

When Ravenous Rats enters, target opponent discards a card.

Gray Merchant of Asphodel

When Gray Merchant of Asphodel enters, each opponent loses X life, where X is your devotion to black. You gain life equal to the life lost this way. (Each {B} in the mana costs of permanents you control counts toward your devotion to black.)

Plains

Momentary Blink

Exile target creature you control, then return it to the battlefield under its owner's control.
Flashback {3}{U} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Rotting Rats

When Rotting Rats enters, each player discards a card.
Unearth {1}{B} ({1}{B}: Return this card from your graveyard to the battlefield. It gains haste. Exile it at the beginning of the next end step or if it would leave the battlefield. Unearth only as a sorcery.)

Flicker of Fate

Exile target creature or enchantment, then return it to the battlefield under its owner's control.

Ephemerate

Exile target creature you control, then return it to the battlefield under its owner's control.
Rebound (If you cast this spell from your hand, exile it as it resolves. At the beginning of your next upkeep, you may cast this card from exile without paying its mana cost.)

Chittering Rats

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