Breeding Pool

({T}: Add {G} or {U}.)
As Breeding Pool enters the battlefield, you may pay 2 life. If you don't, it enters the battlefield tapped.

Halo Hopper

Convoke (Your creatures can help cast this spell. Each creature you tap while casting this spell pays for {1} or one mana of that creature's color.)

Rejuvenating Springs

Rejuvenating Springs enters the battlefield tapped unless you have two or more opponents.
{T}: Add {G} or {U}.

Codex Shredder

{T}: Target player mills a card. (They put the top card of their library into their graveyard.)
{5}, {T}, Sacrifice Codex Shredder: Return target card from your graveyard to your hand.

Rampant Growth

Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Laboratory Maniac

If you would draw a card while your library has no cards in it, you win the game instead.

Evolving Wilds

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

Growth Spiral

Draw a card. You may put a land card from your hand onto the battlefield.

Counterspell

Temple of Mystery

Temple of Mystery enters the battlefield tapped.
When Temple of Mystery enters the battlefield, scry 1.
{T}: Add {G} or {U}.

Turn to Frog

Until end of turn, target creature loses all abilities and becomes a blue Frog with base power and toughness 1/1.

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.

Hedge Maze

({T}: Add {G} or {U}.)
Hedge Maze enters the battlefield tapped.
When Hedge Maze enters the battlefield, surveil 1. (Look at the top card of your library. You may put it into your graveyard.)

Doc Aurlock, Grizzled Genius

Spells you cast from your graveyard or from exile cost {2} less to cast.
Plotting cards from your hand costs {2} less.

Jace, Wielder of Mysteries

If you would draw a card while your library has no cards in it, you win the game instead.
+1: Target player mills two cards. Draw a card.
−8: Draw seven cards. Then if your library has no cards in it, you win the game.

Thassa's Oracle

When Thassa's Oracle enters the battlefield, look at the top X cards of your library, where X is your devotion to blue. Put up to one of them on top of your library and the rest on the bottom of your library in a random order. If X is greater than or equal to the number of cards in your library, you win the game. (Each {U} in the mana costs of permanents you control counts toward your devotion to blue.)

Hermit Druid

{G}, {T}: Reveal cards from the top of your library until you reveal a basic land card. Put that card into your hand and all other cards revealed this way into your graveyard.

Traumatize

Target player mills half their library, rounded down.

Elvish Mystic

Cut Your Losses

Casualty 2 (As you cast this spell, you may sacrifice a creature with power 2 or greater. When you do, copy this spell and you may choose a new target for the copy.)
Target player mills half their library, rounded down.

Croaking Counterpart

Create a token that's a copy of target non-Frog creature, except it's a 1/1 green Frog.
Flashback {3}{G}{U} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Dreamroot Cascade

Dreamroot Cascade enters the battlefield tapped unless you control two or more other lands.
{T}: Add {G} or {U}.

Leapfrog

Leapfrog has flying as long as you've cast an instant or sorcery spell this turn.

Command Tower

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

Beast Within

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

Crocanura

Reach (This creature can block creatures with flying.)
Evolve (Whenever a creature enters the battlefield under your control, if that creature has greater power or toughness than this creature, put a +1/+1 counter on this creature.)

Azusa, Lost but Seeking

You may play two additional lands on each of your turns.

Haze Frog

Flash (You may cast this spell any time you could cast an instant.)
When Haze Frog enters the battlefield, prevent all combat damage that other creatures would deal this turn.

Frogify

Enchant creature
Enchanted creature loses all abilities and is a blue Frog creature with base power and toughness 1/1. (It loses all other card types and creature types.)

Omnibian

{T}: Target creature becomes a Frog with base power and toughness 3/3 until end of turn.

Spring Splasher

Whenever Spring Splasher attacks, target creature defending player controls gets -3/-0 until end of turn.

Arcane Signet

Mesmeric Orb

Whenever a permanent becomes untapped, that permanent's controller mills a card.

Druidic Ritual

You may mill three cards. Then return up to one creature card and up to one land card from your graveyard to your hand. (To mill a card, put the top card of your library into your graveyard.)

Sol Ring

Hedron Crab

Landfall — Whenever a land enters the battlefield under your control, target player mills three cards.

Willow Geist

Trample
Whenever one or more cards leave your graveyard, put a +1/+1 counter on Willow Geist.
When Willow Geist dies, you gain life equal to its power.

Froghemoth

Trample, haste
Whenever Froghemoth deals combat damage to a player, exile up to that many target cards from their graveyard. Put a +1/+1 counter on Froghemoth for each creature card exiled this way. You gain 1 life for each noncreature card exiled this way.

Thought Scour

Target player mills two cards.
Draw a card.

Swiftfoot Boots

Equipped creature has hexproof and haste. (It can't be the target of spells or abilities your opponents control.)
Equip {1}

Court of Cunning

When Court of Cunning enters the battlefield, you become the monarch.
At the beginning of your upkeep, any number of target players each mill two cards. If you're the monarch, each of those players mills ten cards instead. (To mill a card, a player puts the top card of their library into their graveyard.)

Tamiyo, Collector of Tales

Spells and abilities your opponents control can't cause you to discard cards or sacrifice permanents.
+1: Choose a nonland card name, then reveal the top four cards of your library. Put all cards with the chosen name from among them into your hand and the rest into your graveyard.
−3: Return target card from your graveyard to your hand.

Grolnok, the Omnivore

Whenever a Frog you control attacks, mill three cards.
Whenever a permanent card is put into your graveyard from your library, exile it with a croak counter on it.
You may play lands and cast spells from among cards you own in exile with croak counters on them.

Simic Growth Chamber

Simic Growth Chamber enters the battlefield tapped.
When Simic Growth Chamber enters the battlefield, return a land you control to its owner's hand.
{T}: Add {G}{U}.

Crawling Sensation

At the beginning of your upkeep, you may mill two cards.
Whenever one or more land cards are put into your graveyard from anywhere for the first time each turn, create a 1/1 green Insect creature token.

Eternal Witness

When Eternal Witness enters the battlefield, you may return target card from your graveyard to your hand.

Chalk Outline

Whenever one or more creature cards leave your graveyard, create a 2/2 white and blue Detective creature token, then investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: Draw a card.")

Exotic Orchard

{T}: Add one mana of any color that a land an opponent controls could produce.

Exploration

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

Deranged Assistant

{T}, Mill a card: Add {C}. (To mill a card, put the top card of your library into your graveyard.)

Forest

Trollbred Guardian

{2}{G}: Adapt 2. (If this creature has no +1/+1 counters on it, put two +1/+1 counters on it.)
Each creature you control with a +1/+1 counter on it has trample.

Poison Dart Frog

Reach
{T}: Add one mana of any color.
{2}: Poison Dart Frog gains deathtouch until end of turn.

Millikin

Rapid Hybridization

Destroy target creature. It can't be regenerated. That creature's controller creates a 3/3 green Frog Lizard creature token.

Desecrated Tomb

Whenever one or more creature cards leave your graveyard, create a 1/1 black Bat creature token with flying.

Whiptongue Frog

{U}: Whiptongue Frog gains flying until end of turn.

Lightning Greaves

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

Island

Plaxcaster Frogling

Graft 3 (This creature enters the battlefield with three +1/+1 counters on it. Whenever another creature enters the battlefield, you may move a +1/+1 counter from this creature onto it.)
{2}: Target creature with a +1/+1 counter on it gains shroud until end of turn. (It can't be the target of spells or abilities.)

Crawling Infestation

At the beginning of your upkeep, you may mill two cards. (You may put the top two cards of your library into your graveyard.)
Whenever one or more creature cards are put into your graveyard from anywhere during your turn, create a 1/1 green Insect creature token. This ability triggers only once each turn.

Perpetual Timepiece

{T}: Mill two cards.
{2}, Exile Perpetual Timepiece: Shuffle any number of target cards from your graveyard into your library.

Cyclonic Rift

Return target nonland permanent you don't control to its owner's hand.
Overload {6}{U} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Tangled Islet

({T}: Add {G} or {U}.)
Tangled Islet enters the battlefield tapped.

Kasmina's Transmutation

Enchant creature
Enchanted creature loses all abilities and has base power and toughness 1/1.

Path of Ancestry

Path of Ancestry enters the battlefield tapped.
{T}: Add one mana of any color in your commander's color identity. When that mana is spent to cast a creature spell that shares a creature type with your commander, scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Llanowar Elves

Papercraft Decoy

When Papercraft Decoy leaves the battlefield, you may pay {2}. If you do, draw a card.

Witness Protection

Enchant creature
Enchanted creature loses all abilities and is a green and white Citizen creature with base power and toughness 1/1 named Legitimate Businessperson. (It loses all other colors, card types, creature types, and names.)

Jade Avenger

Bushido 2 (Whenever this creature blocks or becomes blocked, it gets +2/+2 until end of turn.)

Simic Signet

Talisman of Curiosity

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

Roaming Throne

Ward {2}
As Roaming Throne enters the battlefield, choose a creature type.
Roaming Throne is the chosen type in addition to its other types.
If a triggered ability of another creature you control of the chosen type triggers, it triggers an additional time.

Polymorphist's Jest

Until end of turn, each creature target player controls loses all abilities and becomes a blue Frog with base power and toughness 1/1.

Burrog Befuddler

Flash
When Burrog Befuddler enters the battlefield, target creature an opponent controls gets -1/-0 until end of turn.

Murkfiend Liege

Other green creatures you control get +1/+1.
Other blue creatures you control get +1/+1.
Untap all green and/or blue creatures you control during each other player's untap step.

Eaten by Piranhas

Flash
Enchant creature
Enchanted creature loses all abilities and is a black Skeleton creature with base power and toughness 1/1. (It loses all other card types and creature types.)

Galloping Lizrog

Trample
When Galloping Lizrog enters the battlefield, you may remove any number of +1/+1 counters from among creatures you control. If you do, put twice that many +1/+1 counters on Galloping Lizrog.

Otherworldly Gaze

Surveil 3. (Look at the top three cards of your library, then put any number of them into your graveyard and the rest on top of your library in any order.)
Flashback {1}{U} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Spore Frog

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

Yavimaya Coast

{T}: Add {C}.
{T}: Add {G} or {U}. Yavimaya Coast deals 1 damage to you.

Hinterland Harbor

Hinterland Harbor enters the battlefield tapped unless you control a Forest or an Island.
{T}: Add {G} or {U}.