Demonic Taskmaster

Flying
At the beginning of your upkeep, sacrifice a creature other than this creature.

Wretched Anurid

Whenever another creature enters, you lose 1 life.

Counterspell

Greater Harvester

At the beginning of your upkeep, sacrifice a permanent.
Whenever this creature deals combat damage to a player, that player sacrifices two permanents of their choice.

Abyssal Persecutor

Flying, trample
You can't win the game and your opponents can't lose the game.

Perplexing Chimera

Whenever an opponent casts a spell, you may exchange control of this creature and that spell. If you do, you may choose new targets for the spell. (If the spell becomes a permanent, you control that permanent.)

Arcane Signet

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

Thought Vessel

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

Ebonblade Reaper

Whenever this creature attacks, you lose half your life, rounded up.
Whenever this creature deals combat damage to a player, that player loses half their life, rounded up.
Morph {3}{B}{B} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)

Archfiend of the Dross

Flying
This creature enters with four oil counters on it.
At the beginning of your upkeep, remove an oil counter from this creature. 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.

Propaganda

Creatures can't attack you unless their controller pays {2} for each creature they control that's attacking you.

Flesh Reaver

Whenever this creature deals damage to a creature or opponent, this creature deals that much damage to you.

Lightning Greaves

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

Swiftfoot Boots

Equipped creature has hexproof and haste. (It can't be the target of spells or abilities your opponents control. It can attack and {T} no matter when it came under your control.)
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Steel Golem

Rotting Regisaur

At the beginning of your upkeep, discard a card.

Jon Irenicus, Shattered One

At the beginning of your end step, target opponent gains control of up to one target creature you control. Put two +1/+1 counters on it and tap it. It's goaded for the rest of the game and it gains "This creature can't be sacrificed." (It attacks each combat if able and attacks a player other than you if able.)
Whenever a creature you own but don't control attacks, you draw a card.

Ebon Drake

Flying
Whenever a player casts a spell, you lose 1 life.

Plague Reaver

At the beginning of your end step, sacrifice each other creature you control.
Discard two cards, Sacrifice this creature: Choose target opponent. Return this creature to the battlefield under that player's control at the beginning of their next upkeep.

Negate

Sol Ring

Sisay, Weatherlight Captain

Sisay gets +1/+1 for each color among other legendary permanents you control.
{W}{U}{B}{R}{G}: Search your library for a legendary permanent card with mana value less than Sisay's power, put that card onto the battlefield, then shuffle.

Evil Eye of Urborg

Non-Eye creatures you control can't attack.
Whenever this creature becomes blocked by a creature, destroy that creature.

Drinker of Sorrow

This creature can't block.
Whenever this creature deals combat damage, sacrifice a permanent.

Exchange of Words

When this enchantment enters, choose two target creatures. For as long as this enchantment remains on the battlefield, exchange the text boxes of those creatures.