Swamp

Pestilence

At the beginning of the end step, if no creatures are on the battlefield, sacrifice this enchantment.
{B}: This enchantment deals 1 damage to each creature and each player.

Mind Rake

Target player discards two cards.
Overload {1}{B} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Grave Scrabbler

Madness {1}{B} (If you discard this card, discard it into exile. When you do, cast it for its madness cost or put it into your graveyard.)
When this creature enters, if its madness cost was paid, you may return target creature card from a graveyard to its owner's hand.

Clay Revenant

This creature enters tapped.
{2}{B}: Return this card from your graveyard to your hand.

Sanitarium Skeleton

{2}{B}: Return this card from your graveyard to your hand.

Witch's Cauldron

{1}{B}, {T}, Sacrifice a creature: You gain 1 life and draw a card.

Delirium Skeins

Retrofitted Transmogrant

{3}{B}: Return this card from your graveyard to the battlefield tapped with two +1/+1 counters on it.

Mountain

Persistent Specimen

{2}{B}: Return this card from your graveyard to the battlefield tapped.

Faithless Looting

Draw two cards, then discard two cards.
Flashback {2}{R} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Last Rites

Discard any number of cards. Target player reveals their hand, then you choose a nonland card from it for each card discarded this way. That player discards those cards.