Varolz, the Scar-Striped

Each creature card in your graveyard has scavenge. The scavenge cost is equal to its mana cost. (Exile a creature card from your graveyard and pay its mana cost: Put a number of +1/+1 counters equal to that card's power on target creature. Scavenge only as a sorcery.)
Sacrifice another creature: Regenerate Varolz, the Scar-Striped.

Satyr Wayfinder

When Satyr Wayfinder enters the battlefield, reveal the top four cards of your library. You may put a land card from among them into your hand. Put the rest into your graveyard.

Cartel Aristocrat

Sacrifice another creature: Cartel Aristocrat gains protection from the color of your choice until end of turn.

Cauldron Familiar

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

Yahenni, Undying Partisan

Haste
Whenever a creature an opponent controls dies, put a +1/+1 counter on Yahenni, Undying Partisan.
Sacrifice another creature: Yahenni gains indestructible until end of turn.

Stitcher's Supplier

When Stitcher's Supplier enters the battlefield or dies, mill three cards.

Dusk Legion Zealot

When Dusk Legion Zealot enters the battlefield, you draw a card and you lose 1 life.

Cruel Celebrant

Whenever Cruel Celebrant or another creature or planeswalker you control dies, each opponent loses 1 life and you gain 1 life.

Rally the Ancestors

Return each creature card with mana value X or less from your graveyard to the battlefield. Exile those creatures at the beginning of your next upkeep. Exile Rally the Ancestors.

Elvish Visionary

When Elvish Visionary enters the battlefield, draw a card.

Witch's Oven

{T}, Sacrifice a creature: Create a Food token. If the sacrificed creature's toughness was 4 or greater, create two Food tokens instead. (They're artifacts with "{2}, {T}, Sacrifice this artifact: You gain 3 life.")

Glowspore Shaman

When Glowspore Shaman enters the battlefield, mill three cards. You may put a land card from your graveyard on top of your library. (To mill a card, put the top card of your library into your graveyard.)

Priest of Forgotten Gods

{T}, Sacrifice two other creatures: Any number of target players each lose 2 life and sacrifice a creature. You add {B}{B} and draw a card.

Collected Company

Look at the top six cards of your library. Put up to two creature cards with mana value 3 or less from among them onto the battlefield. Put the rest on the bottom of your library in any order.

Zulaport Cutthroat

Whenever Zulaport Cutthroat or another creature you control dies, each opponent loses 1 life and you gain 1 life.

Corpse Knight

Whenever another creature enters the battlefield under your control, each opponent loses 1 life.