Sanitarium Skeleton

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

Crypt Rats

{X}: Crypt Rats deals X damage to each creature and each player. Spend only black mana on X.

Obsidian Acolyte

Protection from black
{W}: Target creature gains protection from black until end of turn.

Cauldron Familiar

When Cauldron Familiar enters, each opponent loses 1 life and you gain 1 life.
Sacrifice a Food: Return Cauldron Familiar from your graveyard to the battlefield.

Tortured Existence

{B}, Discard a creature card: Return target creature card from your graveyard to your hand.

Sakura-Tribe Elder

Sacrifice Sakura-Tribe Elder: Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Crawling Infestation

At the beginning of your upkeep, you may mill two cards. (You may put the top two cards of your library into your graveyard.)
Whenever one or more creature cards are put into your graveyard from anywhere during your turn, create a 1/1 green Insect creature token. This ability triggers only once each turn.

Pestilence

At the beginning of the end step, if no creatures are on the battlefield, sacrifice Pestilence.
{B}: Pestilence deals 1 damage to each creature and each player.

Bartered Cow

When Bartered Cow dies or when you discard it, create a Food token. (It's an artifact with "{2}, {T}, Sacrifice this artifact: You gain 3 life.")

Auramancer

When Auramancer enters, you may return target enchantment card from your graveyard to your hand.

Wastes

Unexpected Fangs

Put a +1/+1 counter and a lifelink counter on target creature.

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.")

Heaped Harvest

When Heaped Harvest enters and when you sacrifice it, you may search your library for a basic land card, put it onto the battlefield tapped, then shuffle.
{2}, {T}, Sacrifice Heaped Harvest: You gain 3 life.

Arboreal Grazer

Reach
When Arboreal Grazer enters, you may put a land card from your hand onto the battlefield tapped.