Clement, the Worrywort

Vigilance
Whenever Clement, the Worrywort or another creature you control enters, return up to one target creature you control with lesser mana value to its owner's hand.
Frogs you control have "{T}: Add {G} or {U}. Spend this mana only to cast a creature spell."

Command Tower

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

Evolving Wilds

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

Forest

Island

Terramorphic Expanse

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

Bellowing Crier

When Bellowing Crier enters, draw a card, then discard a card.

Clifftop Lookout

Reach
When Clifftop Lookout enters, reveal cards from the top of your library until you reveal a land card. Put that card onto the battlefield tapped and the rest on the bottom of your library in a random order.

Dour Port-Mage

Whenever one or more other creatures you control leave the battlefield without dying, draw a card.
{1}{U}, {T}: Return another target creature you control to its owner's hand.

Dreamdew Entrancer

Reach
When Dreamdew Entrancer enters, tap up to one target creature and put three stun counters on it. If you control that creature, draw two cards.

Lilysplash Mentor

Reach
{1}{G}{U}: Exile another target creature you control, then return it to the battlefield under its owner's control with a +1/+1 counter on it. Activate only as a sorcery.

Long River Lurker

Ward {1}
Other Frogs you control have ward {1}.
When Long River Lurker enters, target creature you control can't be blocked this turn. Whenever that creature deals combat damage this turn, you may exile it. If you do, return it to the battlefield under its owner's control.

Mistbreath Elder

At the beginning of your upkeep, return another creature you control to its owner's hand. If you do, put a +1/+1 counter on Mistbreath Elder. Otherwise, you may return Mistbreath Elder to its owner's hand.

Pond Prophet

Skyskipper Duo

Flying
When Skyskipper Duo enters, exile up to one other target creature you control. Return it to the battlefield under its owner's control at the beginning of the next end step.

Splash Lasher

Offspring {1}{U} (You may pay an additional {1}{U} as you cast this spell. If you do, when this creature enters, create a 1/1 token copy of it.)
When this creature enters, tap up to one target creature and put a stun counter on it. (If a permanent with a stun counter would become untapped, remove one from it instead.)

Stickytongue Sentinel

Reach
When Stickytongue Sentinel enters, return up to one other target permanent you control to its owner's hand.

Sunshower Druid

When Sunshower Druid enters, put a +1/+1 counter on target creature and you gain 1 life.

Three Tree Scribe

Whenever Three Tree Scribe or another creature you control leaves the battlefield without dying, put a +1/+1 counter on target creature you control.

Treeguard Duo

When Treeguard Duo enters, until end of turn, target creature you control gains vigilance and gets +X/+X, where X is the number of creatures you control.

Valley Mightcaller

Trample
Whenever another Frog, Rabbit, Raccoon, or Squirrel you control enters, put a +1/+1 counter on Valley Mightcaller.

Waterspout Warden

Whenever Waterspout Warden attacks, if another creature entered the battlefield under your control this turn, Waterspout Warden gains flying until end of turn.

Lilypad Village

{T}: Add {C}.
{T}: Add {U}. Spend this mana only to cast a creature spell.
{U}, {T}: Surveil 2. Activate only if a Bird, Frog, Otter, or Rat entered the battlefield under your control this turn.

Polliwallop

This spell costs {1} less to cast for each Frog you control.
Target creature you control deals damage equal to twice its power to target creature you don't control.

Splash Portal

Exile target creature you control, then return it to the battlefield under its owner's control. If that creature is a Bird, Frog, Otter, or Rat, draw a card.

Barkform Harvester

Changeling (This card is every creature type.)
Reach
{2}: Put target card from your graveyard on the bottom of your library.

Calamitous Tide

Return up to two target creatures to their owners' hands. Draw two cards, then discard a card.

Dazzling Denial

Counter target spell unless its controller pays {2}. If you control a Bird, counter that spell unless its controller pays {4} instead.

Dire Downdraft

This spell costs {1} less to cast if it targets an attacking or tapped creature.
Target creature's owner puts it on the top or bottom of their library.

Gossip's Talent

(Gain the next level as a sorcery to add its ability.)
Whenever a creature you control enters, surveil 1.
{1}{U}: Level 2
Whenever you attack, target attacking creature with power 3 or less can't be blocked this turn.
{3}{U}: Level 3
Whenever a creature you control deals combat damage to a player, you may exile it, then return it to the battlefield under its owner's control.

Kitnap

Gift a card (You may promise an opponent a gift as you cast this spell. If you do, when it enters, they draw a card.)
Enchant creature
When Kitnap enters, tap enchanted creature. If the gift wasn't promised, put three stun counters on it.
You control enchanted creature.

Long River's Pull

Gift a card (You may promise an opponent a gift as you cast this spell. If you do, they draw a card before its other effects.)
Counter target creature spell. If the gift was promised, instead counter target spell.

Mockingbird

Flying
You may have Mockingbird enter as a copy of any creature on the battlefield with mana value less than or equal to the amount of mana spent to cast Mockingbird, except it's a Bird in addition to its other types and it has flying.

Plumecreed Escort

Flash
Flying
When Plumecreed Escort enters, target creature you control gains hexproof until end of turn.

Run Away Together

Choose two target creatures controlled by different players. Return those creatures to their owners' hands.

Season of Weaving

Choose up to five {P} worth of modes. You may choose the same mode more than once.
{P} — Draw a card.
{P}{P} — Choose an artifact or creature you control. Create a token that's a copy of it.
{P}{P}{P} — Return each nonland, nontoken permanent to its owner's hand.

Three Tree Mascot

Changeling (This card is every creature type.)
{1}: Add one mana of any color. Activate only once each turn.

Sugar Coat

Flash
Enchant creature or Food
Enchanted permanent is a colorless Food artifact with "{2}, {T}, Sacrifice this artifact: You gain 3 life" and loses all other card types and abilities.

Galewind Moose

Overprotect

Target creature you control gets +3/+3 and gains trample, hexproof, and indestructible until end of turn.

Hivespine Wolverine

When Hivespine Wolverine enters, choose one —
• Put a +1/+1 counter on target creature you control.
• Hivespine Wolverine fights target creature token.
• Destroy target artifact or enchantment.

Eluge, the Shoreless Sea

Eluge's power and toughness are each equal to the number of Islands you control.
Whenever Eluge enters or attacks, put a flood counter on target land. It's an Island in addition to its other types for as long as it has a flood counter on it.
The first instant or sorcery spell you cast each turn costs {U} (or {1}) less to cast for each land you control with a flood counter on it.

Fabled Passage

{T}, Sacrifice Fabled Passage: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle. Then if you control four or more lands, untap that land.

Three Tree City

As Three Tree City enters, choose a creature type.
{T}: Add {C}.
{2}, {T}: Choose a color. Add an amount of mana of that color equal to the number of creatures you control of the chosen type.

Uncharted Haven

Uncharted Haven enters tapped. As it enters, choose a color.
{T}: Add one mana of the chosen color.

Oakhollow Village

{T}: Add {C}.
{T}: Add {G}. Spend this mana only to cast a creature spell.
{G}, {T}: Put a +1/+1 counter on each Frog, Rabbit, Raccoon, or Squirrel you control that entered the battlefield this turn.

When this creature enters, tap up to one target creature and put a stun counter on it.
(This token's mana cost is {3}{U}.)

Copy

(This token can be used to represent a token that's a copy of a permanent.)

Restless Vinestalk

Restless Vinestalk enters tapped.
{T}: Add {G} or {U}.
{3}{G}{U}: Until end of turn, Restless Vinestalk becomes a 5/5 green and blue Plant creature with trample. It's still a land.
Whenever Restless Vinestalk attacks, up to one other target creature has base power and toughness 3/3 until end of turn.