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.

Flesh Carver

Intimidate (This creature can't be blocked except by artifact creatures and/or creatures that share a color with it.)
{1}{B}, Sacrifice another creature: Put two +1/+1 counters on Flesh Carver.
When Flesh Carver dies, create an X/X black Horror creature token, where X is Flesh Carver's power.

Tezzeret's Gambit

({U/P} can be paid with either {U} or 2 life.)
Draw two cards, then proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Evolving Wilds

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

Animal Sanctuary

{T}: Add {C}.
{2}, {T}: Put a +1/+1 counter on target Bird, Cat, Dog, Goat, Ox, or Snake.

Chitterspitter

At the beginning of your upkeep, you may sacrifice a token. If you do, put an acorn counter on Chitterspitter.
Squirrels you control get +1/+1 for each acorn counter on Chitterspitter.
{G}, {T}: Create a 1/1 green Squirrel creature token.

Exploration

You may play an additional land on each of your turns.

Conspiracy

As Conspiracy enters the battlefield, choose a creature type.
Creatures you control are the chosen type. The same is true for creature spells you control and creature cards you own that aren't on the battlefield.

Lifecraft Awakening

Put X +1/+1 counters on target artifact you control. If it isn't a creature or Vehicle, it becomes a 0/0 Construct artifact creature.

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.

Migratory Route

Create four 1/1 white Bird creature tokens with flying.
Basic landcycling {2} ({2}, Discard this card: Search your library for a basic land card, reveal it, put it into your hand, then shuffle.)

Battle Screech

Create two 1/1 white Bird creature tokens with flying.
Flashback—Tap three untapped white creatures you control. (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Avatar of Growth

This spell costs {1} less to cast for each opponent you have.
Trample
When Avatar of Growth enters the battlefield, each player searches their library for up to two basic land cards, puts them onto the battlefield, then shuffles.

Kangee, Aerie Keeper

Kicker {X}{2} (You may pay an additional {X}{2} as you cast this spell.)
Flying
When Kangee, Aerie Keeper enters the battlefield, if it was kicked, put X feather counters on it.
Other Bird creatures get +1/+1 for each feather counter on Kangee, Aerie Keeper.

Phyrexian Tower

{T}: Add {C}.
{T}, Sacrifice a creature: Add {B}{B}.

Plains

Baral, Chief of Compliance

Instant and sorcery spells you cast cost {1} less to cast.
Whenever a spell or ability you control counters a spell, you may draw a card. If you do, discard a card.

Ilysian Caryatid

{T}: Add one mana of any color. If you control a creature with power 4 or greater, add two mana of any one color instead.

Squirrel Sanctuary

When Squirrel Sanctuary enters the battlefield, create a 1/1 green Squirrel creature token.
Whenever a nontoken creature you control dies, you may pay {1}. If you do, return Squirrel Sanctuary to its owner's hand.

Urborg, Tomb of Yawgmoth

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

Ashnod's Altar

Wall of Runes

Defender (This creature can't attack.)
When Wall of Runes enters the battlefield, scry 1. (Look at the top card of your library. You may put that card on the bottom of your library.)

Chatter of the Squirrel

Create a 1/1 green Squirrel creature token.
Flashback {1}{G} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Squirrel Sovereign

Chatterstorm

Create a 1/1 green Squirrel creature token.
Storm (When you cast this spell, copy it for each spell cast before it this turn.)

Squirrel Dealer

When Squirrel Dealer enters the battlefield, ask a person outside the game "Do you like Squirrels?" If they do, create a 1/1 green Squirrel creature token.

Empyrean Eagle

Flying
Other creatures you control with flying get +1/+1.

Swarmyard

{T}: Add {C}.
{T}: Regenerate target Insect, Rat, Spider, or Squirrel. (The next time it would be destroyed, instead tap it, remove it from combat, and heal all damage on it.)

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.)

The Mending of Dominaria

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I, II — Mill two cards, then you may return a creature card from your graveyard to your hand.
III — Return all land cards from your graveyard to the battlefield, then shuffle your graveyard into your library.

Counterspell

Luminous Broodmoth

Flying
Whenever a creature you control without flying dies, return it to the battlefield under its owner's control with a flying counter on it.

Myr Scrapling

Sacrifice Myr Scrapling: Put a +1/+1 counter on target creature.

Gift of Doom

Enchant creature
Enchanted creature has deathtouch and indestructible.
Morph—Sacrifice another creature. (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)
As Gift of Doom is turned face up, you may attach it to a creature.

Xenograft

As Xenograft enters the battlefield, choose a creature type.
Each creature you control is the chosen type in addition to its other types.

Sungrass Prairie

Dark Ritual

Thoughtcast

Affinity for artifacts (This spell costs {1} less to cast for each artifact you control.)
Draw two cards.

Skullclamp

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

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.)

Parallel Lives

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

Aven Brigadier

Flying
Other Bird creatures get +1/+1.
Other Soldier creatures get +1/+1.

Squirrel Nest

Enchant land
Enchanted land has "{T}: Create a 1/1 green Squirrel creature token."

Squirrel Mob

Squirrel Mob gets +1/+1 for each other Squirrel on the battlefield.

Inventors' Fair

At the beginning of your upkeep, if you control three or more artifacts, you gain 1 life.
{T}: Add {C}.
{4}, {T}, Sacrifice Inventors' Fair: Search your library for an artifact card, reveal it, put it into your hand, then shuffle. Activate only if you control three or more artifacts.

Ishai, Ojutai Dragonspeaker

Flying
Whenever an opponent casts a spell, put a +1/+1 counter on Ishai, Ojutai Dragonspeaker.
Partner (You can have two commanders if both have partner.)

Veteran Explorer

When Veteran Explorer dies, each player may search their library for up to two basic land cards, put them onto the battlefield, then shuffle.

Brainstorm

Draw three cards, then put two cards from your hand on top of your library in any order.

Reyhan, Last of the Abzan

Reyhan, Last of the Abzan enters the battlefield with three +1/+1 counters on it.
Whenever a creature you control dies or is put into the command zone, if it had one or more +1/+1 counters on it, you may put that many +1/+1 counters on target creature.
Partner (You can have two commanders if both have partner.)

Urban Daggertooth

Vigilance
Enrage — Whenever Urban Daggertooth is dealt damage, proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Diamond Lion

{T}, Discard your hand, Sacrifice Diamond Lion: Add three mana of any one color. Activate only as an instant.

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}.

Retreat to Kazandu

Landfall — Whenever a land enters the battlefield under your control, choose one —
• Put a +1/+1 counter on target creature.
• You gain 2 life.

Jeweled Lotus

{T}, Sacrifice Jeweled Lotus: Add three mana of any one color. Spend this mana only to cast your commander.

Shimmer Myr

Flash
You may cast artifact spells as though they had flash.

Forest

Chatterfang, Squirrel General

Forestwalk (This creature can't be blocked as long as defending player controls a Forest.)
If one or more tokens would be created under your control, those tokens plus that many 1/1 green Squirrel creature tokens are created instead.
{B}, Sacrifice X Squirrels: Target creature gets +X/-X until end of turn.

Skycloud Expanse

Contagion Engine

When Contagion Engine enters the battlefield, put a -1/-1 counter on each creature target player controls.
{4}, {T}: Proliferate twice. (Choose any number of permanents and/or players, then give each another counter of each kind already there. Then do it again.)

Sol Ring

Lotus Petal

{T}, Sacrifice Lotus Petal: Add one mana of any color.

Orzhov Signet

Swamp

Darkwater Catacombs

Solemn Simulacrum

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

Elesh Norn, Grand Cenobite

Vigilance
Other creatures you control get +2/+2.
Creatures your opponents control get -2/-2.

Smell Fear

Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)
Target creature you control fights up to one target creature you don't control.

Island

Gilder Bairn

{2}{G/U}, {Q}: Double the number of each kind of counter on target permanent. ({Q} is the untap symbol.)

Liliana of the Dark Realms

+1: Search your library for a Swamp card, reveal it, put it into your hand, then shuffle.
−3: Target creature gets +X/+X or -X/-X until end of turn, where X is the number of Swamps you control.
−6: You get an emblem with "Swamps you control have '{T}: Add {B}{B}{B}{B}.'"

Fabricate

Search your library for an artifact card, reveal it, put it into your hand, then shuffle.

Soulcatchers' Aerie

Whenever a Bird is put into your graveyard from the battlefield, put a feather counter on Soulcatchers' Aerie.
Bird creatures get +1/+1 for each feather counter on Soulcatchers' Aerie.

Sakura-Tribe Scout

{T}: You may put a land card from your hand onto the battlefield.

Primal Vigor

If one or more tokens would be created, twice that many of those tokens are created instead.
If one or more +1/+1 counters would be put on a creature, twice that many +1/+1 counters are put on that creature instead.

Command Beacon

{T}: Add {C}.
{T}, Sacrifice Command Beacon: Put your commander into your hand from the command zone.

Roc Egg

Defender (This creature can't attack.)
When Roc Egg dies, create a 3/3 white Bird creature token with flying.

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.)

Clockwork Condor

Flying
Clockwork Condor enters the battlefield with three +1/+1 counters on it.
Whenever Clockwork Condor attacks or blocks, remove a +1/+1 counter from it at end of combat.

Esper Sentinel

Whenever an opponent casts their first noncreature spell each turn, draw a card unless that player pays {X}, where X is Esper Sentinel's power.

Propaganda

Creatures can't attack you unless their controller pays {2} for each creature they control that's attacking you.

Wall of Mist

Azorius Signet

Ravenous Squirrel

Whenever you sacrifice an artifact or creature, put a +1/+1 counter on Ravenous Squirrel.
{1}{B}{G}, Sacrifice an artifact or creature: You gain 1 life and draw a card.