Gixian Infiltrator

Whenever you sacrifice another permanent, put a +1/+1 counter on Gixian Infiltrator.

Vampire's Bite

Kicker {2}{B} (You may pay an additional {2}{B} as you cast this spell.)
Target creature gets +3/+0 until end of turn. If this spell was kicked, that creature gains lifelink until end of turn. (Damage dealt by the creature also causes its controller to gain that much life.)

Blood Fountain

When Blood Fountain enters, create a Blood token. (It's an artifact with "{1}, {T}, Discard a card, Sacrifice this artifact: Draw a card.")
{3}{B}, {T}, Sacrifice Blood Fountain: Return up to two target creature cards from your graveyard to your hand.

Serrated Scorpion

When Serrated Scorpion dies, it deals 2 damage to each opponent and you gain 2 life.

Shambling Ghast

When Shambling Ghast dies, choose one —
• Target creature an opponent controls gets -1/-1 until end of turn.
• Create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Gurmag Angler

Delve (Each card you exile from your graveyard while casting this spell pays for {1}.)

Bone Shards

As an additional cost to cast this spell, sacrifice a creature or discard a card.
Destroy target creature or planeswalker.

Omen of the Dead

Flash
When Omen of the Dead enters, return target creature card from your graveyard to your hand.
{2}{B}, Sacrifice Omen of the Dead: Scry 2.

Corrupted Conviction

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

Swamp

Infestation Sage

When this creature dies, create a 1/1 black and green Insect creature token with flying.

Vampire's Kiss

Target player loses 2 life and you gain 2 life. Create two Blood tokens. (They're artifacts with "{1}, {T}, Discard a card, Sacrifice this artifact: Draw a card.")