Sengir Vampire

Flying (This creature can't be blocked except by creatures with flying or reach.)
Whenever a creature dealt damage by Sengir Vampire this turn dies, put a +1/+1 counter on Sengir Vampire.

Ob Nixilis's Cruelty

Target creature gets -5/-5 until end of turn. If that creature would die this turn, exile it instead.

Swamp

Debtors' Transport

Afterlife 2 (When this creature dies, create two 1/1 white and black Spirit creature tokens with flying.)

Deadly Dispute

As an additional cost to cast this spell, sacrifice an artifact or creature.
Draw two cards and create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Costly Plunder

As an additional cost to cast this spell, sacrifice an artifact or creature.
Draw two cards.

Festering Mummy

When Festering Mummy dies, you may put a -1/-1 counter on target creature.

Doomed Dissenter

When Doomed Dissenter dies, create a 2/2 black Zombie creature token.

Lethal Sting

As an additional cost to cast this spell, put a -1/-1 counter on a creature you control.
Destroy target creature.

Altar's Reap

As an additional cost to cast this spell, sacrifice a creature.
Draw two cards.

Sanitarium Skeleton

{2}{B}: Return Sanitarium Skeleton from your graveyard to your hand.

Dire Fleet Hoarder

When Dire Fleet Hoarder dies, create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Skymarch Bloodletter

Flying
When Skymarch Bloodletter enters, target opponent loses 1 life and you gain 1 life.

Undercity Scavenger

When Undercity Scavenger enters, you may sacrifice another creature. If you do, put two +1/+1 counters on Undercity Scavenger, then scry 2.

Bone Splinters

As an additional cost to cast this spell, sacrifice a creature.
Destroy target creature.