Harmless Offering

Target opponent gains control of target permanent you control.

Coveted Falcon

Flying
Whenever Coveted Falcon attacks, gain control of target permanent you own but don't control.
Disguise {1}{U}
When Coveted Falcon is turned face up, target opponent gains control of any number of target permanents you control. Draw a card for each one they gained control of this way.

Negate

Greed's Gambit

When Greed's Gambit enters, you draw three cards, gain 6 life, and create three 2/1 black Bat creature tokens with flying.
At the beginning of your end step, you discard a card, lose 2 life, and sacrifice a creature.
When Greed's Gambit leaves the battlefield, you discard three cards, lose 6 life, and sacrifice three creatures.

Spirebluff Canal

Spirebluff Canal enters tapped unless you control two or fewer other lands.
{T}: Add {U} or {R}.

Demonic Pact

At the beginning of your upkeep, choose one that hasn't been chosen —
• This enchantment deals 4 damage to any target and you gain 4 life.
• Target opponent discards two cards.
• Draw two cards.
• You lose the game.

Blackcleave Cliffs

Blackcleave Cliffs enters tapped unless you control two or fewer other lands.
{T}: Add {B} or {R}.

Abrade

Choose one —
• Abrade deals 3 damage to target creature.
• Destroy target artifact.

Darkslick Shores

Darkslick Shores enters tapped unless you control two or fewer other lands.
{T}: Add {U} or {B}.

Archfiend of the Dross

Flying
Archfiend of the Dross enters with four oil counters on it.
At the beginning of your upkeep, remove an oil counter from Archfiend of the Dross. Then if it has no oil counters on it, you lose the game.
Whenever a creature an opponent controls dies, its controller loses 2 life.