Flesh Reaver

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

Thought Eater

Flying
Your maximum hand size is reduced by three.

Abyssal Persecutor

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

Phyrexian Negator

Trample
Whenever this creature is dealt damage, sacrifice that many permanents.

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.

Crawlspace

No more than two creatures can attack you each combat.

Steel Golem

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.)

Taniwha

Trample
Phasing (This phases in or out before you untap during each of your untap steps. While it's phased out, it's treated as though it doesn't exist.)
At the beginning of your upkeep, all lands you control phase out. (They phase in before you untap during your next untap step.)

Demonic Taskmaster

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

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.

Grid Monitor

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.