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.

Fatal Push

Destroy target creature if it has mana value 2 or less.
Revolt — Destroy that creature if it has mana value 4 or less instead if a permanent you controlled left the battlefield this turn.

Attune with Aether

Search your library for a basic land card, reveal it, put it into your hand, then shuffle. You get {E}{E} (two energy counters).

Urborg, Tomb of Yawgmoth

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

Mazirek, Kraul Death Priest

Flying
Whenever a player sacrifices another permanent, put a +1/+1 counter on each creature you control.

Grave Betrayal

Whenever a creature you don't control dies, return it to the battlefield under your control with an additional +1/+1 counter on it at the beginning of the next end step. That creature is a black Zombie in addition to its other colors and types.

Cultivate

Search your library for up to two basic land cards, reveal those cards, put one onto the battlefield tapped and the other into your hand, then shuffle.

Liege of the Tangle

Trample
Whenever Liege of the Tangle deals combat damage to a player, you may choose any number of target lands you control and put an awakening counter on each of them. Each of those lands is an 8/8 green Elemental creature for as long as it has an awakening counter on it. They're still lands.

Filth

Swampwalk (This creature can't be blocked as long as defending player controls a Swamp.)
As long as Filth is in your graveyard and you control a Swamp, creatures you control have swampwalk.

Swamp

Jet Medallion

Black spells you cast cost {1} less to cast.

Polluted Mire

Polluted Mire enters tapped.
{T}: Add {B}.
Cycling {2} ({2}, Discard this card: Draw a card.)

Read the Bones

Scry 2, then draw two cards. You lose 2 life. (To scry 2, look at the top two cards of your library, then put any number of them on the bottom and the rest on top in any order.)

Hissing Quagmire

Hissing Quagmire enters tapped.
{T}: Add {B} or {G}.
{1}{B}{G}: Hissing Quagmire becomes a 2/2 black and green Elemental creature with deathtouch until end of turn. It's still a land.

Blooming Marsh

Blooming Marsh enters tapped unless you control two or fewer other lands.
{T}: Add {B} or {G}.

Rune-Scarred Demon

Flying
When this creature enters, search your library for a card, put it into your hand, then shuffle.

Hornet Queen

Flying, deathtouch
When Hornet Queen enters, create four 1/1 green Insect creature tokens with flying and deathtouch.

Lotleth Troll

Trample
Discard a creature card: Put a +1/+1 counter on Lotleth Troll.
{B}: Regenerate Lotleth Troll.

Life's Finale

Destroy all creatures, then search target opponent's library for up to three creature cards and put them into their graveyard. Then that player shuffles.

Buried Alive

Search your library for up to three creature cards, put them into your graveyard, then shuffle.

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.

Eldrazi Conscription

Enchant creature
Enchanted creature gets +10/+10 and has trample and annihilator 2. (Whenever it attacks, defending player sacrifices two permanents of their choice.)

Gonti, Lord of Luxury

Deathtouch
When Gonti, Lord of Luxury enters, look at the top four cards of target opponent's library, exile one of them face down, then put the rest on the bottom of that library in a random order. You may cast that card for as long as it remains exiled, and mana of any type can be spent to cast that spell.

Slippery Karst

Slippery Karst enters tapped.
{T}: Add {G}.
Cycling {2} ({2}, Discard this card: Draw a card.)

Deathrite Shaman

{T}: Exile target land card from a graveyard. Add one mana of any color.
{B}, {T}: Exile target instant or sorcery card from a graveyard. Each opponent loses 2 life.
{G}, {T}: Exile target creature card from a graveyard. You gain 2 life.

Diabolic Tutor

Search your library for a card, put that card into your hand, then shuffle.

Putrefy

Destroy target artifact or creature. It can't be regenerated.

Hornet Nest

Defender (This creature can't attack.)
Whenever Hornet Nest is dealt damage, create that many 1/1 green Insect creature tokens with flying and deathtouch. (Any amount of damage a creature with deathtouch deals to a creature is enough to destroy it.)

Grave Titan

Deathtouch
Whenever Grave Titan enters or attacks, create two 2/2 black Zombie creature tokens.

Thoughtseize

Target player reveals their hand. You choose a nonland card from it. That player discards that card. You lose 2 life.

Kodama's Reach

Commander's Sphere

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

Viscera Seer

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

Forest

Spore Frog

Sacrifice Spore Frog: Prevent all combat damage that would be dealt this turn.

Jarad, Golgari Lich Lord

Jarad, Golgari Lich Lord gets +1/+1 for each creature card in your graveyard.
{1}{B}{G}, Sacrifice another creature: Each opponent loses life equal to the sacrificed creature's power.
Sacrifice a Swamp and a Forest: Return Jarad from your graveyard to your hand.

Evolving Wilds

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

Meren of Clan Nel Toth

Whenever another creature you control dies, you get an experience counter.
At the beginning of your end step, choose target creature card in your graveyard. If that card's mana value is less than or equal to the number of experience counters you have, return it to the battlefield. Otherwise, put it into your hand.

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.

Attrition

{B}, Sacrifice a creature: Destroy target nonblack creature.

Harmonize

Jarad's Orders

Search your library for up to two creature cards and reveal them. Put one into your hand and the other into your graveyard. Then shuffle.

Wall of Blossoms

Defender
When Wall of Blossoms enters, draw a card.

Tainted Wood

{T}: Add {C}.
{T}: Add {B} or {G}. Activate only if you control a Swamp.

Command Tower

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

Puppeteer Clique

Flying
When Puppeteer Clique enters, put target creature card from an opponent's graveyard onto the battlefield under your control. It gains haste. At the beginning of your next end step, exile it.
Persist (When this creature dies, if it had no -1/-1 counters on it, return it to the battlefield under its owner's control with a -1/-1 counter on it.)

Butcher of Malakir

Flying
Whenever Butcher of Malakir or another creature you control dies, each opponent sacrifices a creature of their choice.

Sidisi, Undead Vizier

Deathtouch
Exploit (When this creature enters, you may sacrifice a creature.)
When Sidisi, Undead Vizier exploits a creature, you may search your library for a card, put it into your hand, then shuffle.

Merciless Executioner

When Merciless Executioner enters, each player sacrifices a creature of their choice.

Grim Backwoods

{T}: Add {C}.
{2}{B}{G}, {T}, Sacrifice a creature: Draw a card.

Solemn Simulacrum

When this creature enters, you may search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.
When this creature dies, you may draw a card.

Ravenous Chupacabra

When Ravenous Chupacabra enters, destroy target creature an opponent controls.

Thief of Blood

Flying
As Thief of Blood enters, remove all counters from all permanents. Thief of Blood enters with a +1/+1 counter on it for each counter removed this way.

Arachnogenesis

Create X 1/2 green Spider creature tokens with reach, where X is the number of creatures attacking you. Prevent all combat damage that would be dealt this turn by non-Spider creatures.

Oblivion Stone

{4}, {T}: Put a fate counter on target permanent.
{5}, {T}, Sacrifice Oblivion Stone: Destroy each nonland permanent without a fate counter on it, then remove all fate counters from all permanents.

Blood Artist

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

Mycoloth

Devour 2 (As this enters, you may sacrifice any number of creatures. This creature enters with twice that many +1/+1 counters on it.)
At the beginning of your upkeep, create a 1/1 green Saproling creature token for each +1/+1 counter on Mycoloth.

Sakura-Tribe Elder

Sacrifice Sakura-Tribe Elder: Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

High Market

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

Lightning Greaves

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

Satyr Wayfinder

When Satyr Wayfinder enters, 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.

Jungle Hollow

This land enters tapped.
When this land enters, you gain 1 life.
{T}: Add {B} or {G}.

Gaze of Granite

Destroy each nonland permanent with mana value X or less.

Murder

Phyrexian Delver

When Phyrexian Delver enters, return target creature card from your graveyard to the battlefield. You lose life equal to that card's mana value.

Caustic Caterpillar

{1}{G}, Sacrifice Caustic Caterpillar: Destroy target artifact or enchantment.

Sol Ring

Noxious Gearhulk

Menace
When Noxious Gearhulk enters, you may destroy another target creature. If a creature is destroyed this way, you gain life equal to its toughness.

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.")

Sepulchral Primordial

Intimidate (This creature can't be blocked except by artifact creatures and/or creatures that share a color with it.)
When Sepulchral Primordial enters, for each opponent, you may put up to one target creature card from that player's graveyard onto the battlefield under your control.

Phyrexian Arena

At the beginning of your upkeep, you draw a card and you lose 1 life.

Gray Merchant of Asphodel

When Gray Merchant of Asphodel enters, each opponent loses X life, where X is your devotion to black. You gain life equal to the life lost this way. (Each {B} in the mana costs of permanents you control counts toward your devotion to black.)

Dictate of Erebos

Flash
Whenever a creature you control dies, each opponent sacrifices a creature of their choice.

Ghoulcaller Gisa

{B}, {T}, Sacrifice another creature: Create X 2/2 black Zombie creature tokens, where X is the sacrificed creature's power.

Awakening Zone

At the beginning of your upkeep, you may create a 0/1 colorless Eldrazi Spawn creature token. It has "Sacrifice this creature: Add {C}."

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.

Sheoldred, Whispering One

Swampwalk (This creature can't be blocked as long as defending player controls a Swamp.)
At the beginning of your upkeep, return target creature card from your graveyard to the battlefield.
At the beginning of each opponent's upkeep, that player sacrifices a creature of their choice.

Golgari Rot Farm

Golgari Rot Farm enters tapped.
When Golgari Rot Farm enters, return a land you control to its owner's hand.
{T}: Add {B}{G}.

Terastodon

When Terastodon enters, you may destroy up to three target noncreature permanents. For each permanent put into a graveyard this way, its controller creates a 3/3 green Elephant creature token.