Hydra's Growth

Enchant creature
When Hydra's Growth enters, put a +1/+1 counter on enchanted creature.
At the beginning of your upkeep, double the number of +1/+1 counters on enchanted creature.

Resolute Reinforcements

Flash (You may cast this spell any time you could cast an instant.)
When this creature enters, create a 1/1 white Soldier creature token.

Wildwood Mentor

Whenever a token you control enters, put a +1/+1 counter on Wildwood Mentor.
Whenever Wildwood Mentor attacks, another target attacking creature gets +X/+X until end of turn, where X is Wildwood Mentor's power.

Rabble Rousing

Hideaway 5 (When this enchantment enters, look at the top five cards of your library, exile one face down, then put the rest on the bottom in a random order.)
Whenever you attack with one or more creatures, create that many 1/1 green and white Citizen creature tokens. Then if you control ten or more creatures, you may play the exiled card without paying its mana cost.

Plains

Cadira, Caller of the Small

Trample
Whenever Cadira, Caller of the Small deals combat damage to a player, for each token you control, create a 1/1 white Rabbit creature token.

Sungrass Prairie

Bess, Soul Nourisher

Whenever one or more other creatures you control with base power and toughness 1/1 enter, put a +1/+1 counter on Bess, Soul Nourisher.
Whenever Bess attacks, each other creature you control with base power and toughness 1/1 gets +X/+X until end of turn, where X is the number of +1/+1 counters on Bess.

Lifecrafter's Bestiary

At the beginning of your upkeep, scry 1.
Whenever you cast a creature spell, you may pay {G}. If you do, draw a card.

Generous Gift

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

Commander's Sphere

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

Caustic Caterpillar

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

Genesis Chamber

Whenever a nontoken creature enters, if Genesis Chamber is untapped, that creature's controller creates a 1/1 colorless Myr artifact creature token.

Swiftfoot Boots

Equipped creature has hexproof and haste. (It can't be the target of spells or abilities your opponents control. It can attack and {T} no matter when it came under your control.)
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Pledge of Unity

Put a +1/+1 counter on each creature you control. You gain 1 life for each creature you control.

Cathars' Crusade

Whenever a creature you control enters, put a +1/+1 counter on each creature you control.

Fyndhorn Elves

Oketra's Monument

White creature spells you cast cost {1} less to cast.
Whenever you cast a creature spell, create a 1/1 white Warrior creature token with vigilance.

Elvish Visionary

When Elvish Visionary enters, draw a card.

Selfless Savior

Sacrifice Selfless Savior: Another target creature you control gains indestructible until end of turn. (Damage and effects that say "destroy" don't destroy it.)

Arcane Signet

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

Symmetry Matrix

Whenever a creature you control with power equal to its toughness enters, you may pay {1}. If you do, draw a card.

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.

Servo Exhibition

Create two 1/1 colorless Servo artifact creature tokens.

Conclave Mentor

If one or more +1/+1 counters would be put on a creature you control, that many plus one +1/+1 counters are put on that creature instead.
When Conclave Mentor dies, you gain life equal to its power.

Doomed Traveler

When Doomed Traveler dies, create a 1/1 white Spirit creature token with flying.

Spirit Bonds

Whenever a nontoken creature you control enters, you may pay {W}. If you do, create a 1/1 white Spirit creature token with flying.
{1}{W}, Sacrifice a Spirit: Target non-Spirit creature gains indestructible until end of turn. (Damage and effects that say "destroy" don't destroy it.)

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.)

Animation Module

Whenever one or more +1/+1 counters are put on a permanent you control, you may pay {1}. If you do, create a 1/1 colorless Servo artifact creature token.
{3}, {T}: Choose a counter on target permanent or player. Give that permanent or player another counter of that kind.

Spirited Companion

When Spirited Companion enters, draw a card.

Selesnya Signet

Overrun

Creatures you control get +3/+3 and gain trample until end of turn. (Each of those creatures can deal excess combat damage to the player or planeswalker it's attacking.)

Scute Swarm

Landfall — Whenever a land you control enters, create a 1/1 green Insect creature token. If you control six or more lands, create a token that's a copy of Scute Swarm instead.

Avacyn's Pilgrim

Path to Exile

Exile target creature. Its controller may search their library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Fungal Sprouting

Create X 1/1 green Saproling creature tokens, where X is the greatest power among creatures you control.

Crawling Chorus

Toxic 1 (Players dealt combat damage by this creature also get a poison counter.)
When Crawling Chorus dies, create a 1/1 colorless Phyrexian Mite artifact creature token with toxic 1 and "This creature can't block."

Sundering Growth

Destroy target artifact or enchantment, then populate. (Create a token that's a copy of a creature token you control.)

Invigorating Surge

Put a +1/+1 counter on target creature you control, then double the number of +1/+1 counters on that creature.

Mercy Killing

Target creature's controller sacrifices it, then creates X 1/1 green and white Elf Warrior creature tokens, where X is that creature's power.

Retreat to Emeria

Landfall — Whenever a land you control enters, choose one —
• Create a 1/1 white Kor Ally creature token.
• Creatures you control get +1/+1 until end of turn.

Champion of Lambholt

Creatures with power less than Champion of Lambholt's power can't block creatures you control.
Whenever another creature you control enters, put a +1/+1 counter on Champion of Lambholt.

Gala Greeters

Alliance — Whenever another creature you control enters, choose one that hasn't been chosen this turn —
• Put a +1/+1 counter on Gala Greeters.
• Create a tapped Treasure token.
• You gain 2 life.

Mentor of the Meek

Whenever another creature you control with power 2 or less enters, you may pay {1}. If you do, draw a card.

Forest

Elvish Mystic

Wild Beastmaster

Whenever Wild Beastmaster attacks, each other creature you control gets +X/+X until end of turn, where X is Wild Beastmaster's power.

Torens, Fist of the Angels

Training (Whenever this creature attacks with another creature with greater power, put a +1/+1 counter on this creature.)
Whenever you cast a creature spell, create a 1/1 green and white Human Soldier creature token with training.

Haazda Marshal

Whenever Haazda Marshal and at least two other creatures attack, create a 1/1 white Soldier creature token with lifelink.

Maja, Bretagard Protector

Other creatures you control get +1/+1.
Landfall — Whenever a land you control enters, create a 1/1 white Human Warrior creature token.

Sigil Captain

Whenever a creature you control enters, if that creature is 1/1, put two +1/+1 counters on it.

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.

Command Tower

Healer's Hawk

Flying
Lifelink (Damage dealt by this creature also causes you to gain that much life.)

Sol Ring

Aura Mutation

Destroy target enchantment. Create X 1/1 green Saproling creature tokens, where X is that enchantment's mana value.

Fencing Ace

Double strike (This creature deals both first-strike and regular combat damage.)

Talisman of Unity

{T}: Add {C}.
{T}: Add {G} or {W}. Talisman of Unity deals 1 damage to you.

Luminarch Aspirant

At the beginning of combat on your turn, put a +1/+1 counter on target creature you control.

Managorger Hydra

Trample
Whenever a player casts a spell, put a +1/+1 counter on Managorger Hydra.

Gaea's Gift

Put a +1/+1 counter on target creature you control. It gains reach, trample, hexproof, and indestructible until end of turn. (It can't be the target of spells or abilities your opponents control. Damage and effects that say "destroy" don't destroy it.)

Rosie Cotton of South Lane

When Rosie Cotton of South Lane enters, create a Food token. (It's an artifact with "{2}, {T}, Sacrifice this artifact: You gain 3 life.")
Whenever you create a token, put a +1/+1 counter on target creature you control other than Rosie.

Wyrm's Crossing Patrol

Myriad (Whenever this creature attacks, for each opponent other than defending player, you may create a token copy that's tapped and attacking that player or a planeswalker they control. Exile the tokens at end of combat.)

Jawbone Duelist

Double strike
Toxic 1 (Players dealt combat damage by this creature also get a poison counter.)

Alseid of Life's Bounty

Lifelink
{1}, Sacrifice Alseid of Life's Bounty: Target creature or enchantment you control gains protection from the color of your choice until end of turn.

Haunted Library

Whenever a creature an opponent controls dies, you may pay {1}. If you do, create a 1/1 white Spirit creature token with flying.

Idol of Oblivion

{T}: Draw a card. Activate only if you created a token this turn.
{8}, {T}, Sacrifice Idol of Oblivion: Create a 10/10 colorless Eldrazi creature token.

Sram's Expertise

Create three 1/1 colorless Servo artifact creature tokens.
You may cast a spell with mana value 3 or less from your hand without paying its mana cost.

Llanowar Elves

Benevolent Bodyguard

Sacrifice Benevolent Bodyguard: Target creature you control gains protection from the color of your choice until end of turn.