Arcane Signet

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

Sign in Blood

Target player draws two cards and loses 2 life.

Thrumming Stone

Spells you cast have ripple 4. (Whenever you cast a spell, you may reveal the top four cards of your library. You may cast spells with the same name as that spell from among the revealed cards without paying their mana costs. Put the rest on the bottom of your library.)

Urza's Incubator

As this artifact enters, choose a creature type.
Creature spells of the chosen type cost {2} less to cast.

Umori, the Collector

Companion — Each nonland card in your starting deck shares a card type. (If this card is your chosen companion, you may put it into your hand from outside the game for {3} as a sorcery.)
As Umori enters, choose a card type.
Spells you cast of the chosen type cost {1} less to cast.

Nykthos, Shrine to Nyx

{T}: Add {C}.
{2}, {T}: Choose a color. Add an amount of mana of that color equal to your devotion to that color. (Your devotion to a color is the number of mana symbols of that color in the mana costs of permanents you control.)

Forest

Living Death

Each player exiles all creature cards from their graveyard, then sacrifices all creatures they control, then puts all cards they exiled this way onto the battlefield.

Ravenous Slime

This creature can't be blocked by creatures with power 2 or less.
If a creature an opponent controls would die, instead exile it and put a number of +1/+1 counters equal to that creature's power on this creature.

Green Slime

Flash
When this creature enters, counter target activated or triggered ability from an artifact or enchantment source. If a permanent's ability is countered this way, destroy that permanent.
Foretell {G} (During your turn, you may pay {2} and exile this card from your hand face down. Cast it on a later turn for its foretell cost.)

Damnation

Destroy all creatures. They can't be regenerated.

Sol Ring

Aeve, Progenitor Ooze

Storm (When you cast this spell, copy it for each spell cast before it this turn. Copies become tokens.)
Aeve isn't legendary if it's a token.
Aeve enters with a +1/+1 counter on it for each other Ooze you control.

Death's Presence

Whenever a creature you control dies, put X +1/+1 counters on target creature you control, where X is the power of the creature that died.

Mosswort Bridge

Hideaway 4 (When this land enters, look at the top four cards of your library, exile one face down, then put the rest on the bottom in a random order.)
This land enters tapped.
{T}: Add {G}.
{G}, {T}: You may play the exiled card without paying its mana cost if creatures you control have total power 10 or greater.

Krosan Grip

Split second (As long as this spell is on the stack, players can't cast spells or activate abilities that aren't mana abilities.)
Destroy target artifact or enchantment.

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.)

Swamp

Night's Whisper

Uchuulon

Uchuulon's power is equal to the number of Crabs, Oozes, and/or Horrors you control.
Horrific Symbiosis — At the beginning of your end step, exile up to one target creature card from an opponent's graveyard. If you do, create a token that's a copy of this creature.

Temple of the False God

{T}: Add {C}{C}. Activate only if you control five or more lands.

Gluttonous Slime

Flash
Devour 1 (As this creature enters, you may sacrifice any number of creatures. It enters with that many +1/+1 counters on it.)

Deathcap Glade

This land enters tapped unless you control two or more other lands.
{T}: Add {B} or {G}.

Woodland Chasm

({T}: Add {B} or {G}.)
This land enters tapped.

Reliquary Tower

You have no maximum hand size.
{T}: Add {C}.

Gutter Grime

Whenever a nontoken creature you control dies, put a slime counter on this enchantment, then create a green Ooze creature token with "This token's power and toughness are each equal to the number of slime counters on Gutter Grime."

Falthis, Shadowcat Familiar

Commanders you control have menace and deathtouch.
Partner (You can have two commanders if both have partner.)

Demonic Tutor

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

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.)

Llanowar Wastes

{T}: Add {C}.
{T}: Add {B} or {G}. This land deals 1 damage to you.

Predator Ooze

Indestructible (Damage and effects that say "destroy" don't destroy this creature.)
Whenever this creature attacks, put a +1/+1 counter on it.
Whenever a creature dealt damage by this creature this turn dies, put a +1/+1 counter on this creature.

Overgrown Tomb

({T}: Add {B} or {G}.)
As this land enters, you may pay 2 life. If you don't, it enters tapped.

Opal Palace

{T}: Add {C}.
{1}, {T}: Add one mana of any color in your commander's color identity. If you spend this mana to cast your commander, it enters with a number of additional +1/+1 counters on it equal to the number of times it's been cast from the command zone this game.

Parallel Lives

If an effect would create one or more tokens under your control, it creates twice that many of those tokens instead.

Vampiric Tutor

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

Scavenging Ooze

{G}: Exile target card from a graveyard. If it was a creature card, put a +1/+1 counter on this creature and you gain 1 life.

Slime Against Humanity

Create a 0/0 green Ooze creature token with trample. Put X +1/+1 counters on it, where X is two plus the total number of cards you own in exile and in your graveyard that are Oozes or are named Slime Against Humanity.
A deck can have any number of cards named Slime Against Humanity.

Oran-Rief Ooze

When this creature enters, put a +1/+1 counter on target creature you control.
Whenever this creature attacks, put a +1/+1 counter on each attacking creature with a +1/+1 counter on it.

Urborg, Tomb of Yawgmoth

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

Branching Evolution

If one or more +1/+1 counters would be put on a creature you control, twice that many +1/+1 counters are put on that creature instead.

Woodland Cemetery

This land enters tapped unless you control a Swamp or a Forest.
{T}: Add {B} or {G}.

Vigor

Trample
If damage would be dealt to another creature you control, prevent that damage. Put a +1/+1 counter on that creature for each 1 damage prevented this way.
When Vigor is put into a graveyard from anywhere, shuffle it into its owner's library.

Golgari Signet

Blooming Marsh

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

Verdant Catacombs

{T}, Pay 1 life, Sacrifice this land: Search your library for a Swamp or Forest card, put it onto the battlefield, then shuffle.

Nature's Claim

Destroy target artifact or enchantment. Its controller gains 4 life.

The Ozolith

Whenever a creature you control leaves the battlefield, if it had counters on it, put those counters on The Ozolith.
At the beginning of combat on your turn, if The Ozolith has counters on it, you may move all counters from The Ozolith onto target creature.

Biowaste Blob

Oozes you control get +1/+1.
At the beginning of your upkeep, if you control a commander, create a token that's a copy of this creature.

Command Tower

Phyrexian Arena

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

Oran-Rief, the Vastwood

This land enters tapped.
{T}: Add {G}.
{T}: Put a +1/+1 counter on each green creature that entered this turn.

Talisman of Resilience

{T}: Add {C}.
{T}: Add {B} or {G}. This artifact deals 1 damage to you.

Haunted Mire

Doubling Season

If an effect would create one or more tokens under your control, it creates twice that many of those tokens instead.
If an effect would put one or more counters on a permanent you control, it puts twice that many of those counters on that permanent instead.

Ochre Jelly

Trample
This creature enters with X +1/+1 counters on it.
Split — When this creature dies, if it had two or more +1/+1 counters on it, create a token that's a copy of it at the beginning of the next end step. The token enters with half that many +1/+1 counters on it, rounded down.

Beast Within

Destroy target permanent. Its controller creates a 3/3 green Beast creature token.

Skyshroud Claim

Search your library for up to two Forest cards, put them onto the battlefield, then shuffle.

Undergrowth Stadium

This land enters tapped unless you have two or more opponents.
{T}: Add {B} or {G}.

Cabal Coffers

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

Acidic Slime

Deathtouch (Any amount of damage this deals to a creature is enough to destroy it.)
When this creature enters, destroy target artifact, enchantment, or land.

Mitotic Slime

When this creature dies, create two 2/2 green Ooze creature tokens. They have "When this token dies, create two 1/1 green Ooze creature tokens."

Nature's Lore

Search your library for a Forest card, put that card onto the battlefield, then shuffle.

Myriad Landscape

This land enters tapped.
{T}: Add {C}.
{2}, {T}, Sacrifice this land: Search your library for up to two basic land cards that share a land type, put them onto the battlefield tapped, then shuffle.

Biogenic Ooze

When this creature enters, create a 2/2 green Ooze creature token.
At the beginning of your end step, put a +1/+1 counter on each Ooze you control.
{1}{G}{G}{G}: Create a 2/2 green Ooze creature token.

Slurrk, All-Ingesting

Slurrk enters with five +1/+1 counters on it.
Whenever Slurrk or another creature you control dies, if it had a +1/+1 counter on it, put a +1/+1 counter on each creature you control that has a +1/+1 counter on it.
Partner (You can have two commanders if both have partner.)

Toxic Deluge

As an additional cost to cast this spell, pay X life.
All creatures get -X/-X until end of turn.

Yavimaya, Cradle of Growth

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

Assassin's Trophy

Destroy target permanent an opponent controls. Its controller may search their library for a basic land card, put it onto the battlefield, then shuffle.

Coat of Arms

Each creature gets +1/+1 for each other creature on the battlefield that shares at least one creature type with it. (For example, if two Goblin Warriors and a Goblin Shaman are on the battlefield, each gets +2/+2.)

Three Visits

Search your library for a Forest card, put it onto the battlefield, then shuffle.

Diabolic Intent

As an additional cost to cast this spell, sacrifice a creature.
Search your library for a card, put that card into your hand, then shuffle.

Necroblossom Snarl

As this land enters, you may reveal a Swamp or Forest card from your hand. If you don't, this land enters tapped.
{T}: Add {B} or {G}.