Castle Locthwain

Castle Locthwain enters tapped unless you control a Swamp.
{T}: Add {B}.
{1}{B}{B}, {T}: Draw a card, then you lose life equal to the number of cards in your hand.

Queen Marchesa

Deathtouch, haste
When Queen Marchesa enters, you become the monarch.
At the beginning of your upkeep, if an opponent is the monarch, create a 1/1 black Assassin creature token with deathtouch and haste.

Universal Solvent

{7}, {T}, Sacrifice Universal Solvent: Destroy target permanent.

Reliquary Tower

You have no maximum hand size.
{T}: Add {C}.

Urborg, Tomb of Yawgmoth

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

Doom Blade

Thorn of the Black Rose

Deathtouch
When Thorn of the Black Rose enters, you become the monarch.

Myriad Landscape

Myriad Landscape enters tapped.
{T}: Add {C}.
{2}, {T}, Sacrifice Myriad Landscape: Search your library for up to two basic land cards that share a land type, put them onto the battlefield tapped, then shuffle.

Court of Ambition

When Court of Ambition enters, you become the monarch.
At the beginning of your upkeep, each opponent loses 3 life unless they discard a card. If you're the monarch, instead each opponent loses 6 life unless they discard two cards.

Phyrexian Arena

At the beginning of your upkeep, you draw a card and you lose 1 life.

Emberwilde Captain

When Emberwilde Captain enters, you become the monarch.
Whenever an opponent attacks you while you're the monarch, Emberwilde Captain deals damage to that player equal to the number of cards in their hand.

Return to Dust

Exile target artifact or enchantment. If you cast this spell during your main phase, you may exile up to one other target artifact or enchantment.

Lightning Greaves

Equipped creature has haste and shroud. (It can't be the target of spells or abilities.)
Equip {0}

Feast of Succession

All creatures get -4/-4 until end of turn. You become the monarch.

Cabal Ritual

Add {B}{B}{B}.
Threshold — Add {B}{B}{B}{B}{B} instead if seven or more cards are in your graveyard.

Command Tower

{T}: Add one mana of any color in your commander's color identity.

Marble Diamond

Marble Diamond enters tapped.
{T}: Add {W}.

Cast Down

Path of Ancestry

Path of Ancestry enters tapped.
{T}: Add one mana of any color in your commander's color identity. When that mana is spent to cast a creature spell that shares a creature type with your commander, scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Briarblade Adept

Whenever Briarblade Adept attacks, target creature an opponent controls gets -1/-1 until end of turn.
Encore {3}{B} ({3}{B}, Exile this card from your graveyard: For each opponent, create a token copy that attacks that opponent this turn if able. They gain haste. Sacrifice them at the beginning of the next end step. Activate only as a sorcery.)

Fire Diamond

Fire Diamond enters tapped.
{T}: Add {R}.

Charcoal Diamond

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

Eyeblight Assassin

When Eyeblight Assassin enters, target creature an opponent controls gets -1/-1 until end of turn.