Swamp

Unmask

You may exile a black card from your hand rather than pay this spell's mana cost.
Target player reveals their hand. You choose a nonland card from it. That player discards that card.

Charcoal Diamond

Charcoal Diamond enters tapped.
{T}: Add {B}.

Powder Keg

At the beginning of your upkeep, you may put a fuse counter on Powder Keg.
{T}, Sacrifice Powder Keg: Destroy each artifact and creature with mana value equal to the number of fuse counters on Powder Keg.

Each player loses a third of their life, then discards a third of the cards in their hand, then sacrifices a third of the creatures they control of their choice, then sacrifices a third of the lands they control of their choice. Round up each time.

Mishra's Factory

{T}: Add {C}.
{1}: Mishra's Factory becomes a 2/2 Assembly-Worker artifact creature until end of turn. It's still a land.
{T}: Target Assembly-Worker creature gets +1/+1 until end of turn.

Dark Ritual

Mox Diamond

If Mox Diamond would enter, you may discard a land card instead. If you do, put Mox Diamond onto the battlefield. If you don't, put it into its owner's graveyard.
{T}: Add one mana of any color.

Cabal Therapy

Choose a nonland card name. Target player reveals their hand and discards all cards with that name.
Flashback—Sacrifice a creature. (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Duress

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

Wasteland

{T}: Add {C}.
{T}, Sacrifice Wasteland: Destroy target nonbasic land.

Nether Spirit

At the beginning of your upkeep, if Nether Spirit is the only creature card in your graveyard, you may return Nether Spirit to the battlefield.

Chimeric Idol

{0}: Tap all lands you control. Chimeric Idol becomes a 3/3 Turtle artifact creature until end of turn.