Mordenkainen's Polymorph

Until end of turn, target creature becomes a Dragon with base power and toughness 4/4 and gains flying. (It loses all other creature types.)

Green Dragon

Flying
Poison Breath — When Green Dragon enters, until end of turn, whenever a creature an opponent controls is dealt damage, destroy it.

Collector Ouphe

Activated abilities of artifacts can't be activated.

Air-Cult Elemental

Flying
Whirlwind — When Air-Cult Elemental enters, return up to one other target creature to its owner's hand.

Temple of the Dragon Queen

As Temple of the Dragon Queen enters, you may reveal a Dragon card from your hand. Temple of the Dragon Queen enters tapped unless you revealed a Dragon card this way or you control a Dragon.
As Temple of the Dragon Queen enters, choose a color.
{T}: Add one mana of the chosen color.

Koma, Cosmos Serpent

This spell can't be countered.
At the beginning of each upkeep, create a 3/3 blue Serpent creature token named Koma's Coil.
Sacrifice another Serpent: Choose one —
• Tap target permanent. Its activated abilities can't be activated this turn.
• Koma, Cosmos Serpent gains indestructible until end of turn.

Lurking Roper

Lurking Roper doesn't untap during your untap step.
Whenever you gain life, untap Lurking Roper.

Primordial Wurm

Forest

True Polymorph

Target artifact or creature becomes a copy of another target artifact or creature.

Owlbear

Trample
Keen Senses — When Owlbear enters, draw a card.

Circle of the Moon Druid

Bear Form — During your turn, Circle of the Moon Druid is a Bear with base power and toughness 4/2. (It loses all other creature types.)

Charging Badger

Scaled Herbalist

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

Littjara Mirrorlake

Littjara Mirrorlake enters tapped.
{T}: Add {U}.
{2}{G}{G}{U}, {T}, Sacrifice Littjara Mirrorlake: Create a token that's a copy of target creature you control, except it enters with an additional +1/+1 counter on it. Activate only as a sorcery.

Woodland Stream

Woodland Stream enters tapped.
{T}: Add {G} or {U}.

Coiling Oracle

When Coiling Oracle enters, reveal the top card of your library. If it's a land card, put it onto the battlefield. Otherwise, put that card into your hand.

Caustic Caterpillar

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

Sporeweb Weaver

Reach, hexproof from blue
Whenever Sporeweb Weaver is dealt damage, you gain 1 life and create a 1/1 green Saproling creature token.

Island

Displacer Beast

When Displacer Beast enters, venture into the dungeon. (Enter the first room or advance to the next room.)
Displacement — {3}{U}: Return Displacer Beast to its owner's hand.

Circle of Dreams Druid

{T}: Add {G} for each creature you control.

Varis, Silverymoon Ranger

Reach, ward {1}
Whenever you cast a creature or planeswalker spell, venture into the dungeon. This ability triggers only once each turn. (To venture into the dungeon, enter the first room or advance to the next room.)
Whenever you complete a dungeon, create a 2/2 green Wolf creature token.

Jaspera Sentinel

Reach
{T}, Tap an untapped creature you control: Add one mana of any color.

Clone

You may have Clone enter as a copy of any creature on the battlefield.

Purple Worm

This spell costs {2} less to cast if a creature died this turn.
Ward {2} (Whenever this creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays {2}.)

Kraken of the Straits

Creatures with power less than the number of Islands you control can't block Kraken of the Straits.

Acidic Slime

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

Trufflesnout

When Trufflesnout enters, choose one —
• Put a +1/+1 counter on Trufflesnout.
• You gain 4 life.

Bulette

At the beginning of your end step, if a creature died this turn, put a +1/+1 counter on Bulette.

Pixie Guide

Flying
Grant an Advantage — If you would roll one or more dice, instead roll that many dice plus one and ignore the lowest roll.

Wall of Blossoms

Defender
When Wall of Blossoms enters, draw a card.

Noble Quarry

Bestow {5}{G} (If you cast this card for its bestow cost, it's an Aura spell with enchant creature. It becomes a creature again if it's not attached to a creature.)
All creatures able to block Noble Quarry or enchanted creature do so.
Enchanted creature gets +1/+1.

Intrepid Outlander

Reach
Pack tactics — Whenever Intrepid Outlander attacks, if you attacked with creatures with total power 6 or greater this combat, venture into the dungeon. (Enter the first room or advance to the next room.)

Sakura-Tribe Elder

Sacrifice Sakura-Tribe Elder: Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Rootless Yew

When Rootless Yew dies, search your library for a creature card with power or toughness 6 or greater, reveal it, put it into your hand, then shuffle.

Ellywick Tumblestrum

+1: Venture into the dungeon. (Enter the first room or advance to the next room.)
−2: Look at the top six cards of your library. You may reveal a creature card from among them and put it into your hand. If it's legendary, you gain 3 life. Put the rest on the bottom of your library in a random order.
−7: You get an emblem with "Creatures you control have trample and haste and get +2/+2 for each differently named dungeon you've completed."

Simic Growth Chamber

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

You Happen On a Glade

Choose one —
• Journey On — Search your library for up to two basic land cards, reveal them, put them into your hand, then shuffle.
• Make Camp — Return target permanent card from your graveyard to your hand.

Dungeon Descent

Dungeon Descent enters tapped.
{T}: Add {C}.
{4}, {T}, Tap an untapped legendary creature you control: Venture into the dungeon. Activate only as a sorcery. (Enter the first room or advance to the next room.)

Dire Wolf Prowler

{1}{G}: Dire Wolf Prowler gets +2/+2 and gains haste until end of turn. Activate only once each turn.

Djinni Windseer

Flying
When Djinni Windseer enters, roll a d20.
1—9 | Scry 1.
10—19 | Scry 2.
20 | Scry 3.

Rimeshield Frost Giant

Ward {3} (Whenever this creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays {3}.)

Evolving Wilds

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

Mistral Singer

Flying
Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)

Blue Dragon

Flying
Lightning Breath — When Blue Dragon enters, until your next turn, target creature an opponent controls gets -3/-0, up to one other target creature gets -2/-0, and up to one other target creature gets -1/-0.

Elturgard Ranger

Reach
When Elturgard Ranger enters, create a 2/2 green Wolf creature token.

Underdark Basilisk

Desert of the Indomitable

Desert of the Indomitable enters tapped.
{T}: Add {G}.
Cycling {1}{G} ({1}{G}, Discard this card: Draw a card.)

Sylvan Shepherd

Vigilance
Whenever Sylvan Shepherd attacks, roll a d20.
1—9 | You gain 1 life.
10—19 | You gain 2 life.
20 | You gain 5 life.

Arixmethes, Slumbering Isle

Arixmethes, Slumbering Isle enters tapped with five slumber counters on it.
As long as Arixmethes has a slumber counter on it, it's a land. (It's not a creature.)
Whenever you cast a spell, you may remove a slumber counter from Arixmethes.
{T}: Add {G}{U}.

Iymrith, Desert Doom

Flying
Iymrith, Desert Doom has ward {4} as long as it's untapped.
Whenever Iymrith deals combat damage to a player, draw a card. Then if you have fewer than three cards in hand, draw cards equal to the difference.

Gretchen Titchwillow

{2}{G}{U}: Draw a card. You may put a land card from your hand onto the battlefield.

Rimewood Falls

({T}: Add {G} or {U}.)
Rimewood Falls enters tapped.

Thriving Grove

Thriving Grove enters tapped. As it enters, choose a color other than green.
{T}: Add {G} or one mana of the chosen color.

Mind Flayer

Dominate Monster — When Mind Flayer enters, gain control of target creature for as long as you control Mind Flayer.

Seasons Past

Return any number of cards with different mana values from your graveyard to your hand. Put Seasons Past on the bottom of its owner's library.

Pursued Whale

When Pursued Whale enters, each opponent creates a 1/1 red Pirate creature token with "This creature can't block" and "Creatures you control attack each combat if able."
Spells your opponents cast that target Pursued Whale cost {3} more to cast.

Wild Shape

Choose one. Until end of turn, target creature you control has that base power and toughness, becomes that creature type, and gains that ability.
• 1/3 Turtle with hexproof.
• 1/5 Spider with reach.
• 3/3 Elephant with trample.

You Find a Cursed Idol

Choose one —
• Smash It — Destroy target artifact.
• Lift the Curse — Destroy target enchantment.
• Steal Its Eyes — Create a Treasure token and venture into the dungeon. (Enter the first room or advance to the next room.)

Long Rest

Return X target cards with different mana values from your graveyard to your hand. If eight or more cards were returned to your hand this way, your life total becomes equal to your starting life total. Exile Long Rest.

Natural Order

As an additional cost to cast this spell, sacrifice a green creature.
Search your library for a green creature card, put it onto the battlefield, then shuffle.

Imoti, Celebrant of Bounty

Cascade (When you cast this spell, exile cards from the top of your library until you exile a nonland card that costs less. You may cast it without paying its mana cost. Put the exiled cards on the bottom in a random order.)
Spells you cast with mana value 6 or greater have cascade.

Druid Class

(Gain the next level as a sorcery to add its ability.)
Landfall — Whenever a land you control enters, you gain 1 life.
{2}{G}: Level 2
You may play an additional land on each of your turns.
{4}{G}: Level 3
When this Class becomes level 3, target land you control becomes a creature with haste and "This creature's power and toughness are each equal to the number of lands you control." It's still a land.

Floodtide Serpent

Floodtide Serpent can't attack unless you return an enchantment you control to its owner's hand. (This cost is paid as attackers are declared.)

Gnoll Hunter

Pack tactics — Whenever Gnoll Hunter attacks, if you attacked with creatures with total power 6 or greater this combat, put a +1/+1 counter on Gnoll Hunter.

Loathsome Troll

{3}{G}: Roll a d20. Activate only if Loathsome Troll is in your graveyard.
1—9 | Put Loathsome Troll on top of your library.
10—19 | Return Loathsome Troll to your hand.
20 | Return Loathsome Troll to the battlefield tapped.

Yavimaya Coast

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

Ranger Class

(Gain the next level as a sorcery to add its ability.)
When Ranger Class enters, create a 2/2 green Wolf creature token.
{1}{G}: Level 2
Whenever you attack, put a +1/+1 counter on target attacking creature.
{3}{G}: Level 3
You may look at the top card of your library any time.
You may cast creature spells from the top of your library.

Grunn, the Lonely King

Kicker {3} (You may pay an additional {3} as you cast this spell.)
If Grunn, the Lonely King was kicked, it enters with five +1/+1 counters on it.
Whenever Grunn attacks alone, double its power and toughness until end of turn.

Treasure Vault

{T}: Add {C}.
{X}{X}, {T}, Sacrifice Treasure Vault: Create X Treasure tokens.

Thrashing Brontodon

{1}, Sacrifice this creature: Destroy target artifact or enchantment.

Volo, Guide to Monsters

Whenever you cast a creature spell that doesn't share a creature type with a creature you control or a creature card in your graveyard, copy that spell. (A copy of a creature spell becomes a token.)

Charmed Sleep

Enchant creature
When Charmed Sleep enters, tap enchanted creature.
Enchanted creature doesn't untap during its controller's untap step.

Tidechannel Pathway

Barkchannel Pathway

Barkchannel Pathway // Tidechannel Pathway

Split the Party

Choose target player. Return half the creatures they control to their owner's hand, rounded up.

Neverwinter Dryad

{2}, Sacrifice Neverwinter Dryad: Search your library for a basic Forest card, put it onto the battlefield tapped, then shuffle.

Godhunter Octopus

Godhunter Octopus can't attack unless defending player controls an enchantment or an enchanted permanent.

Wonder

Flying
As long as Wonder is in your graveyard and you control an Island, creatures you control have flying.