Grim Affliction

Put a -1/-1 counter on target creature, then proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Gulping Scraptrap

When Gulping Scraptrap enters or dies, proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Benalish Sleeper

Kicker {B} (You may pay an additional {B} as you cast this spell.)
When Benalish Sleeper enters, if it was kicked, each player sacrifices a creature of their choice.

Nested Shambler

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

Hopeful Vigil

When Hopeful Vigil enters, create a 2/2 white Knight creature token with vigilance.
When Hopeful Vigil is put into a graveyard from the battlefield, scry 2.
{2}{W}: Sacrifice Hopeful Vigil.

Spread the Sickness

Destroy target creature, then proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Hopeless Nightmare

When Hopeless Nightmare enters, each opponent discards a card and loses 2 life.
When Hopeless Nightmare is put into a graveyard from the battlefield, scry 2.
{2}{B}: Sacrifice Hopeless Nightmare.

Carrier Thrall

When Carrier Thrall dies, create a 1/1 colorless Eldrazi Scion creature token. It has "Sacrifice this creature: Add {C}."

Beskir Shieldmate

When Beskir Shieldmate dies, create a 1/1 white Human Warrior creature token.

Exquisite Huntmaster

When Exquisite Huntmaster dies, create a 1/1 green Elf Warrior creature token.
Encore {4}{B} ({4}{B}, Exile this card from your graveyard: For each opponent, create a token copy that attacks that opponent this turn if able. They gain haste. Sacrifice them at the beginning of the next end step. Activate only as a sorcery.)

Evolving Wilds

{T}, Sacrifice this land: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

Viscera Seer

Sacrifice a creature: Scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Hungry Ghoul

{1}, Sacrifice another creature: Put a +1/+1 counter on this creature.

Mintstrosity

When Mintstrosity dies, create a Food token. (It's an artifact with "{2}, {T}, Sacrifice this artifact: You gain 3 life.")

Infestation Sage

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

Carrion Feeder

Carrion Feeder can't block.
Sacrifice a creature: Put a +1/+1 counter on Carrion Feeder.

Garrison Cat

When Garrison Cat dies, create a 1/1 white Human Soldier creature token.

Acolyte of Aclazotz

{T}, Sacrifice another creature or artifact: Each opponent loses 1 life and you gain 1 life.

Bone Shards

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

Whisper of the Dross

Target creature gets -1/-1 until end of turn. Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Minthara, Merciless Soul

Minthara has ward {X}, where X is the number of experience counters you have.
At the beginning of your end step, if a permanent you controlled left the battlefield this turn, you get an experience counter.
Creatures you control get +1/+0 for each experience counter you have.

Martyr for the Cause

When Martyr for the Cause dies, proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Doomed Traveler

When Doomed Traveler dies, create a 1/1 white Spirit creature token with flying.

Eviscerator's Insight

As an additional cost to cast this spell, sacrifice an artifact or creature.
Draw two cards.
Flashback {4}{B} (You may cast this card from your graveyard for its flashback cost and any additional costs. Then exile it.)

Unbounded Potential

Choose one —
• Put a +1/+1 counter on each of up to two target creatures.
• Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)
Entwine {3}{W} (Choose both if you pay the entwine cost.)

Mind Stone

{T}: Add {C}.
{1}, {T}, Sacrifice Mind Stone: Draw a card.

Hunted Witness

When Hunted Witness dies, create a 1/1 white Soldier creature token with lifelink.

Wanderer's Strike

Exile target creature, then proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

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.")

Blightbelly Rat

Toxic 1 (Players dealt combat damage by this creature also get a poison counter.)
When Blightbelly Rat dies, proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Carrot Cake

When Carrot Cake enters and when you sacrifice it, create a 1/1 white Rabbit creature token and scry 1. (Look at the top card of your library. You may put that card on the bottom.)
{2}, {T}, Sacrifice Carrot Cake: You gain 3 life.

Mirkwood Bats

Flying
Whenever you create or sacrifice a token, each opponent loses 1 life.

Crawling Chorus

Toxic 1 (Players dealt combat damage by this creature also get a poison counter.)
When Crawling Chorus dies, create a 1/1 colorless Phyrexian Mite artifact creature token with toxic 1 and "This creature can't block."

Commander's Sphere

{T}: Add one mana of any color in your commander's color identity.
Sacrifice Commander's Sphere: Draw a card.

Discordant Piper

When Discordant Piper dies, create a 0/1 white Goat creature token.

Doomed Dissenter

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

Greedy Freebooter

When Greedy Freebooter dies, scry 1 and create a Treasure token. (To scry 1, look at the top card of your library. You may put that card on the bottom. A Treasure token is an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Cartel Aristocrat

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

Imperious Oligarch

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

Bone Splinters

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

Accursed Marauder

When Accursed Marauder enters, each player sacrifices a nontoken creature of their choice.