Ophiomancer

At the beginning of each upkeep, if you control no Snakes, create a 1/1 black Snake creature token with deathtouch.

Death of a Thousand Stings

Target player loses 1 life and you gain 1 life.
At the beginning of your upkeep, if you have more cards in hand than each opponent, you may return Death of a Thousand Stings from your graveyard to your hand.

Catacomb Slug

Yawgmoth, Thran Physician

Protection from Humans
Pay 1 life, Sacrifice another creature: Put a -1/-1 counter on up to one target creature and draw a card.
{B}{B}, Discard a card: Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

High Market

{T}: Add {C}.
{T}, Sacrifice a creature: You gain 1 life.

Sign in Blood

Target player draws two cards and loses 2 life.

Revel in Riches

Whenever a creature an opponent controls dies, create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")
At the beginning of your upkeep, if you control ten or more Treasures, you win the game.

Urborg, Tomb of Yawgmoth

Each land is a Swamp in addition to its other land types.

Choice of Damnations

Target opponent chooses a number. You may have that player lose that much life. If you don't, that player sacrifices all but that many permanents of their choice.

Village Rites

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

Akroan Horse

Defender
When Akroan Horse enters, an opponent gains control of it.
At the beginning of your upkeep, each opponent creates a 1/1 white Soldier creature token.

Blood Artist

Whenever Blood Artist or another creature dies, target player loses 1 life and you gain 1 life.

Urborg Syphon-Mage

{2}{B}, {T}, Discard a card: Each other player loses 2 life. You gain life equal to the life lost this way.

Slaughter Specialist

When Slaughter Specialist enters, each opponent creates a 1/1 white Human creature token.
Whenever a creature an opponent controls dies, put a +1/+1 counter on Slaughter Specialist.

Leechridden Swamp

({T}: Add {B}.)
Leechridden Swamp enters tapped.
{B}, {T}: Each opponent loses 1 life. Activate only if you control two or more black permanents.

Bitterblossom

At the beginning of your upkeep, you lose 1 life and create a 1/1 black Faerie Rogue creature token with flying.

Black Market

Whenever a creature dies, put a charge counter on Black Market.
At the beginning of your first main phase, add {B} for each charge counter on Black Market.

Talisman of Dominance

{T}: Add {C}.
{T}: Add {U} or {B}. Talisman of Dominance deals 1 damage to you.

Contentious Plan

Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)
Draw a card.

Karn's Bastion

{T}: Add {C}.
{4}, {T}: Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

The Meathook Massacre

When The Meathook Massacre enters, each creature gets -X/-X until end of turn.
Whenever a creature you control dies, each opponent loses 1 life.
Whenever a creature an opponent controls dies, you gain 1 life.

Mana Drain

Counter target spell. At the beginning of your next main phase, add an amount of {C} equal to that spell's mana value.

Lightning Greaves

Equipped creature has haste and shroud. (It can't be the target of spells or abilities.)
Equip {0}

Snow-Covered Island

Toxrill, the Corrosive

At the beginning of each end step, put a slime counter on each creature you don't control.
Creatures you don't control get -1/-1 for each slime counter on them.
Whenever a creature you don't control with a slime counter on it dies, create a 1/1 black Slug creature token.
{U}{B}, Sacrifice a Slug: Draw a card.

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.)

Fuel for the Cause

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

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.

Contagion Clasp

When Contagion Clasp enters, put a -1/-1 counter on target creature.
{4}, {T}: Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Deathgreeter

Whenever another creature dies, you may gain 1 life.

Zulaport Cutthroat

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

Inexorable Tide

Whenever you cast a spell, proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Ashnod's Altar

Gluttonous Slug

Menace
Evolve (Whenever a creature you control enters, if that creature has greater power or toughness than this creature, put a +1/+1 counter on this creature.)

Sakashima of a Thousand Faces

You may have Sakashima of a Thousand Faces enter as a copy of another creature you control, except it has Sakashima of a Thousand Faces's other abilities.
The "legend rule" doesn't apply to permanents you control.
Partner (You can have two commanders if both have partner.)

Nevinyrral's Disk

Nevinyrral's Disk enters tapped.
{1}, {T}: Destroy all artifacts, creatures, and enchantments.

Giant Slug

{5}: At the beginning of your next upkeep, choose a basic land type. Giant Slug gains landwalk of the chosen type until the end of that turn. (It can't be blocked as long as defending player controls a land of that type.)

Skullclamp

Equipped creature gets +1/-1.
Whenever equipped creature dies, draw two cards.
Equip {1}

Fierce Guardianship

If you control a commander, you may cast this spell without paying its mana cost.
Counter target noncreature spell.

Dimir Signet

Swamp

Cabal Coffers

{2}, {T}: Add {B} for each Swamp you control.

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.)

Malakir Cullblade

Whenever a creature an opponent controls dies, put a +1/+1 counter on Malakir Cullblade.

Silumgar's Command

Choose two —
• Counter target noncreature spell.
• Return target permanent to its owner's hand.
• Target creature gets -3/-3 until end of turn.
• Destroy target planeswalker.

Massacre Wurm

When this creature enters, creatures your opponents control get -2/-2 until end of turn.
Whenever a creature an opponent controls dies, that player loses 2 life.

Grave Pact

Whenever a creature you control dies, each other player sacrifices a creature of their choice.

Vampiric Tutor

Search your library for a card, then shuffle and put that card on top. You lose 2 life.

Bastion of Remembrance

When Bastion of Remembrance enters, create a 1/1 white Human Soldier creature token.
Whenever a creature you control dies, each opponent loses 1 life and you gain 1 life.

Blowfly Infestation

Whenever a creature dies, if it had a -1/-1 counter on it, put a -1/-1 counter on target creature.

Sword of Truth and Justice

Equipped creature gets +2/+2 and has protection from white and from blue.
Whenever equipped creature deals combat damage to a player, put a +1/+1 counter on a creature you control, then proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)
Equip {2}

Liliana, Defiant Necromancer

+2: Each player discards a card.
−X: Return target nonlegendary creature card with mana value X from your graveyard to the battlefield.
−8: You get an emblem with "Whenever a creature dies, return it to the battlefield under your control at the beginning of the next end step."

Liliana, Heretical Healer

Lifelink
Whenever another nontoken creature you control dies, exile Liliana, Heretical Healer, then return her to the battlefield transformed under her owner's control. If you do, create a 2/2 black Zombie creature token.

Liliana, Heretical Healer // Liliana, Defiant Necromancer

Counterspell

Helm of the Host

At the beginning of combat on your turn, create a token that's a copy of equipped creature, except the token isn't legendary. That token gains haste.
Equip {5}

Cyclonic Rift

Return target nonland permanent you don't control to its owner's hand.
Overload {6}{U} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Mana Crypt

At the beginning of your upkeep, flip a coin. If you lose the flip, Mana Crypt deals 3 damage to you.
{T}: Add {C}{C}.

Sludge Monster

Whenever Sludge Monster enters or attacks, put a slime counter on up to one other target creature.
Non-Horror creatures with slime counters on them lose all abilities and have base power and toughness 2/2.

Urborg Uprising

Return up to two target creature cards from your graveyard to your hand.
Draw a card.

Steady Progress

Heraldic Banner

As this artifact enters, choose a color.
Creatures you control of the chosen color get +1/+0.
{T}: Add one mana of the chosen color.

Syr Konrad, the Grim

Whenever another creature dies, or a creature card is put into a graveyard from anywhere other than the battlefield, or a creature card leaves your graveyard, Syr Konrad, the Grim deals 1 damage to each opponent.
{1}{B}: Each player mills a card. (They each put the top card of their library into their graveyard.)

Eldrazi Monument

Creatures you control get +1/+1 and have flying and indestructible.
At the beginning of your upkeep, sacrifice a creature. If you can't, sacrifice Eldrazi Monument.

Pitiless Plunderer

Whenever another creature you control dies, create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Vindictive Vampire

Whenever another creature you control dies, Vindictive Vampire deals 1 damage to each opponent and you gain 1 life.

Rhystic Study

Whenever an opponent casts a spell, you may draw a card unless that player pays {1}.

Lolth, Spider Queen

Whenever a creature you control dies, put a loyalty counter on Lolth, Spider Queen.
0: You draw a card and you lose 1 life.
−3: Create two 2/1 black Spider creature tokens with menace and reach.
−8: You get an emblem with "Whenever an opponent is dealt combat damage by one or more creatures you control, if that player lost less than 8 life this turn, they lose life equal to the difference."

Sol Ring

Damnation

Destroy all creatures. They can't be regenerated.

Command Tower

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

Reflections of Littjara

As Reflections of Littjara enters, choose a creature type.
Whenever you cast a spell of the chosen type, copy that spell. (A copy of a permanent spell becomes a token.)