Deathbringer Thoctar

Whenever another creature dies, you may put a +1/+1 counter on this creature.
Remove a +1/+1 counter from this creature: It deals 1 damage to any target.

Totentanz, Swarm Piper

Whenever Totentanz or another nontoken creature you control dies, create a 1/1 black Rat creature token with "This token can't block."
{1}{B}: Target attacking Rat you control gains deathtouch until end of turn.

Balduvian Berserker

Enlist (As this creature attacks, you may tap a nonattacking creature you control without summoning sickness. When you do, add its power to this creature's until end of turn.)
When this creature dies, it deals damage equal to its power to any target.

Hissing Iguanar

Whenever another creature dies, you may have this creature deal 1 damage to target player or planeswalker.

Archetype of Finality

Creatures you control have deathtouch.
Creatures your opponents control lose deathtouch and can't have or gain deathtouch.

Ashcloud Phoenix

Flying
When this creature dies, return it to the battlefield face down under your control.
Morph {4}{R}{R} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)
When this creature is turned face up, it deals 2 damage to each player.

Sticky Fingers

Enchant creature
Enchanted creature has menace and "Whenever this creature deals combat damage to a player, create a Treasure token." (It can't be blocked except by two or more creatures. The token is an artifact with "{T}, Sacrifice this token: Add one mana of any color.")
When enchanted creature dies, draw a card.

Endless Cockroaches

When this creature dies, return it to its owner's hand.

Squee, the Immortal

You may cast this card from your graveyard or from exile.

Touch of Moonglove

Target creature you control gets +1/+0 and gains deathtouch until end of turn. Whenever a creature dealt damage by that creature dies this turn, its controller loses 2 life. (Any amount of damage a creature with deathtouch deals to a creature is enough to destroy it.)

Fake Your Own Death

Until end of turn, target creature gets +2/+0 and gains "When this creature dies, return it to the battlefield tapped under its owner's control and you create a Treasure token." (It's an artifact with "{T}, Sacrifice this token: Add one mana of any color.")

Ninja's Kunai

Equipped creature has "{1}, {T}, Sacrifice Ninja's Kunai: Ninja's Kunai deals 3 damage to any target."
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Novice Occultist

When this creature dies, you draw a card and you lose 1 life.

Greedy Freebooter

When this creature 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 token: Add one mana of any color.")

Voracious Vermin

When this creature enters, create a 1/1 black Rat creature token with "This token can't block."
Whenever another creature you control dies, put a +1/+1 counter on this creature.

Coat with Venom

Target creature gets +1/+2 and gains deathtouch until end of turn. (Any amount of damage it deals to a creature is enough to destroy it.)

Footlight Fiend

When this creature dies, it deals 1 damage to any target.

Lyzolda, the Blood Witch

{2}, Sacrifice a creature: Lyzolda deals 2 damage to any target if the sacrificed creature was red. Draw a card if the sacrificed creature was black.

Cacophony Scamp

Whenever this creature deals combat damage to a player, you may sacrifice it. If you do, proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)
When this creature dies, it deals damage equal to its power to any target.

Arcane Signet

{T}: Add one mana of any color in your commander's color identity.

Judith, the Scourge Diva

Other creatures you control get +1/+0.
Whenever a nontoken creature you control dies, Judith deals 1 damage to any target.

Aetherjacket

Flying, vigilance
{2}, {T}, Sacrifice this creature: Destroy another target artifact. Activate only as a sorcery.

Chainsaw

When this Equipment enters, it deals 3 damage to up to one target creature.
Whenever one or more creatures die, put a rev counter on this Equipment.
Equipped creature gets +X/+0, where X is the number of rev counters on this Equipment.
Equip {3}

Juri, Master of the Revue

Whenever you sacrifice a permanent, put a +1/+1 counter on Juri.
When Juri dies, it deals damage equal to its power to any target.

Mephitic Draught

When this artifact enters or is put into a graveyard from the battlefield, you draw a card and you lose 1 life.

Slobad, Iron Goblin

{T}, Sacrifice an artifact: Add an amount of {R} equal to the sacrificed artifact's mana value. Spend this mana only to cast artifact spells or activate abilities of artifacts.

Vengeful Bloodwitch

Whenever this creature or another creature you control dies, target opponent loses 1 life and you gain 1 life.

Necrosynthesis

Enchant creature
Enchanted creature has "Whenever another creature dies, put a +1/+1 counter on this creature."
When enchanted creature dies, look at the top X cards of your library, where X is its power. Put one of those cards into your hand and the rest on the bottom of your library in a random order.

Supernatural Stamina

Until end of turn, target creature gets +2/+0 and gains "When this creature dies, return it to the battlefield tapped under its owner's control."

Corpse Augur

When this creature dies, you draw X cards and you lose X life, where X is the number of creature cards in target player's graveyard.

Dreadhorde Butcher

Haste
Whenever this creature deals combat damage to a player or planeswalker, put a +1/+1 counter on this creature.
When this creature dies, it deals damage equal to its power to any target.

Illicit Masquerade

Flash
When this enchantment enters, put an impostor counter on each creature you control.
Whenever a creature you control with an impostor counter on it dies, exile it. Return up to one other target creature card from your graveyard to the battlefield.

Showstopper

Until end of turn, creatures you control gain "When this creature dies, it deals 2 damage to target creature an opponent controls."

Rage Thrower

Whenever another creature dies, this creature deals 2 damage to target player or planeswalker.

Sol Ring

Infectious Curse

Enchant player
Spells you cast that target enchanted player cost {1} less to cast.
At the beginning of enchanted player's upkeep, that player loses 1 life and you gain 1 life.

Accursed Witch

Spells your opponents cast that target this creature cost {1} less to cast.
When this creature dies, return it to the battlefield transformed under your control attached to target opponent.

Accursed Witch // Infectious Curse

Reassembling Skeleton

{1}{B}: Return this card from your graveyard to the battlefield tapped.

Spiteful Prankster

During your turn, this creature has first strike.
Whenever another creature dies, this creature deals 1 damage to target player or planeswalker.

Abyssal Gatekeeper

When this creature dies, each player sacrifices a creature of their choice.

Ahriman

Flying, deathtouch
{3}, Sacrifice another creature or artifact: Draw a card.

Nowhere to Run

Flash
When this enchantment enters, target creature an opponent controls gets -3/-3 until end of turn.
Creatures your opponents control can be the targets of spells and abilities as though they didn't have hexproof. Ward abilities of those creatures don't trigger.

Grim Javelineer

Whenever you attack, target attacking creature gets +1/+0 until end of turn. When that creature dies this turn, surveil 1. (Look at the top card of your library. You may put that card into your graveyard.)