Blood Curdle

Destroy target creature. Put a menace counter on a creature you control. (It can't be blocked except by two or more creatures.)

Sewn-Eye Drake

Crosis's Charm

Choose one —
• Return target permanent to its owner's hand.
• Destroy target nonblack creature. It can't be regenerated.
• Destroy target artifact.

Slave of Bolas

Gain control of target creature. Untap that creature. It gains haste until end of turn. Sacrifice it at the beginning of the next end step.

Abaddon the Despoiler

Trample
Mark of Chaos Ascendant — During your turn, spells you cast from your hand with mana value X or less have cascade, where X is the total amount of life your opponents have lost this turn.

Kess, Dissident Mage

Flying
Once during each of your turns, you may cast an instant or sorcery spell from your graveyard. If a spell cast this way would be put into your graveyard, exile it instead.

Elder Mastery

Enchant creature
Enchanted creature gets +3/+3 and has flying.
Whenever enchanted creature deals damage to a player, that player discards two cards.

Kederekt Creeper

Menace (This creature can't be blocked except by two or more creatures.)
Deathtouch (Any amount of damage this deals to a creature is enough to destroy it.)