Diregraf Rebirth

This spell costs {1} less to cast for each creature that died this turn.
Return target creature card from your graveyard to the battlefield.
Flashback {5}{B}{G} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Veteran Explorer

When Veteran Explorer dies, each player may search their library for up to two basic land cards, put them onto the battlefield, then shuffle.

Alter Fate

Return target creature card from your graveyard to your hand. (Then exile this card. You may cast the creature later from exile.)

Order of Midnight

Order of Midnight // Alter Fate

Hunger of the Howlpack

Put a +1/+1 counter on target creature.
Morbid — Put three +1/+1 counters on that creature instead if a creature died this turn.

Thrashing Brontodon

{1}, Sacrifice Thrashing Brontodon: Destroy target artifact or enchantment.

Legion Vanguard

{1}, Sacrifice another creature: Legion Vanguard explores. (Reveal the top card of your library. Put that card into your hand if it's a land. Otherwise, put a +1/+1 counter on this creature, then put the card back or put it into your graveyard.)

Llanowar Elves

Plumb the Forbidden

As an additional cost to cast this spell, you may sacrifice one or more creatures. When you do, copy this spell for each creature sacrificed this way.
You draw a card and you lose 1 life.

Catacomb Sifter

Devoid (This card has no color.)
When Catacomb Sifter enters, create a 1/1 colorless Eldrazi Scion creature token. It has "Sacrifice this creature: Add {C}."
Whenever another creature you control dies, scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Infuse with Vitality

Until end of turn, target creature gains deathtouch and "When this creature dies, return it to the battlefield tapped under its owner's control."
You gain 2 life.

Morbid Opportunist

Whenever one or more other creatures die, draw a card. This ability triggers only once each turn.

Deathreap Ritual

Morbid — At the beginning of each end step, if a creature died this turn, you may draw a card.

Fungal Rebirth

Return target permanent card from your graveyard to your hand. If a creature died this turn, create two 1/1 green Saproling creature tokens.

Tend the Pests

As an additional cost to cast this spell, sacrifice a creature.
Create X 1/1 black and green Pest creature tokens with "When this creature dies, you gain 1 life," where X is the sacrificed creature's power.

Goremand

As an additional cost to cast this spell, sacrifice a creature.
Flying
Trample (This creature can deal excess combat damage to the player or planeswalker it's attacking.)
When Goremand enters, each opponent sacrifices a creature.

Blood Divination

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

Slimefoot, the Stowaway

Whenever a Saproling you control dies, Slimefoot, the Stowaway deals 1 damage to each opponent and you gain 1 life.
{4}: Create a 1/1 green Saproling creature token.

Briarhorn

Flash
When Briarhorn enters, target creature gets +3/+3 until end of turn.
Evoke {1}{G} (You may cast this spell for its evoke cost. If you do, it's sacrificed when it enters.)

Llanowar Visionary

When Llanowar Visionary enters, draw a card.
{T}: Add {G}.

Daemogoth Woe-Eater

At the beginning of your upkeep, sacrifice a creature.
When you sacrifice Daemogoth Woe-Eater, each opponent discards a card, you draw a card, and you gain 2 life.

Owlbear

Trample
Keen Senses — When Owlbear enters, draw a card.

Penumbra Wurm

Trample
When Penumbra Wurm dies, create a 6/6 black Wurm creature token with trample.

Warlock Class

(Gain the next level as a sorcery to add its ability.)
At the beginning of your end step, if a creature died this turn, each opponent loses 1 life.
{1}{B}: Level 2
When this Class becomes level 2, look at the top three cards of your library. Put one of them into your hand and the rest into your graveyard.
{6}{B}: Level 3
At the beginning of your end step, each opponent loses life equal to the life they lost this turn. (Damage causes loss of life.)

Skullmulcher

Devour 1 (As this enters, you may sacrifice any number of creatures. This creature enters with that many +1/+1 counters on it.)
When Skullmulcher enters, draw a card for each creature it devoured.

Corrupted Harvester

{B}, Sacrifice a creature: Regenerate Corrupted Harvester.

Shessra, Death's Whisper

Bewitching Whispers — When Shessra, Death's Whisper enters, target creature blocks this turn if able.
Whispers of the Grave — At the beginning of your end step, if a creature died this turn, you may pay 2 life. If you do, draw a card.

Awoken Demon

Ecstatic Awakener

{2}{B}, Sacrifice another creature: Draw a card, then transform Ecstatic Awakener. Activate only once each turn.

Ecstatic Awakener // Awoken Demon

Nested Shambler

When Nested Shambler dies, create X tapped 1/1 green Squirrel creature tokens, where X is Nested Shambler's power.

Yavimaya Elder

When Yavimaya Elder dies, you may search your library for up to two basic land cards, reveal them, put them into your hand, then shuffle.
{2}, Sacrifice Yavimaya Elder: Draw a card.

Binding the Old Gods

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I — Destroy target nonland permanent an opponent controls.
II — Search your library for a Forest card, put it onto the battlefield tapped, then shuffle.
III — Creatures you control gain deathtouch until end of turn.

Shriekmaw

Fear (This creature can't be blocked except by artifact creatures and/or black creatures.)
When Shriekmaw enters, destroy target nonartifact, nonblack creature.
Evoke {1}{B} (You may cast this spell for its evoke cost. If you do, it's sacrificed when it enters.)

Tragic Slip

Target creature gets -1/-1 until end of turn.
Morbid — That creature gets -13/-13 until end of turn instead if a creature died this turn.

Village Rites

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

Power Word Kill

Destroy target non-Angel, non-Demon, non-Devil, non-Dragon creature.

Caravan Vigil

Search your library for a basic land card, reveal it, put it into your hand, then shuffle.
Morbid — You may put that card onto the battlefield instead of putting it into your hand if a creature died this turn.

Orzhov Enforcer

Deathtouch
Afterlife 1 (When this creature dies, create a 1/1 white and black Spirit creature token with flying.)

Nest Invader

When Nest Invader enters, create a 0/1 colorless Eldrazi Spawn creature token. It has "Sacrifice this creature: Add {C}."

Golgari Guildmage

{4}{B}, Sacrifice a creature: Return target creature card from your graveyard to your hand.
{4}{G}: Put a +1/+1 counter on target creature.

Bayou Groff

As an additional cost to cast this spell, sacrifice a creature or pay {3}.

Ravenous Squirrel

Whenever you sacrifice an artifact or creature, put a +1/+1 counter on Ravenous Squirrel.
{1}{B}{G}, Sacrifice an artifact or creature: You gain 1 life and draw a card.