Neoform

As an additional cost to cast this spell, sacrifice a creature.
Search your library for a creature card with mana value equal to 1 plus the sacrificed creature's mana value, put that card onto the battlefield with an additional +1/+1 counter on it, then shuffle.

Sol Ring

Chakram Retriever

Partner with Chakram Slinger (When this creature enters, target player may put Chakram Slinger into their hand from their library, then shuffle.)
Whenever you cast a spell during your turn, untap target creature.

Greenwarden of Murasa

When this creature enters, you may return target card from your graveyard to your hand.
When this creature dies, you may exile it. If you do, return target card from your graveyard to your hand.

Roalesk, Apex Hybrid

Flying, trample
When Roalesk enters, put two +1/+1 counters on another target creature you control.
When Roalesk dies, proliferate, then proliferate again. (Choose any number of permanents and/or players, then give each another counter of each kind already there. Then do it again.)

Arcane Signet

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

Deceiver Exarch

Flash (You may cast this spell any time you could cast an instant.)
When this creature enters, choose one —
• Untap target permanent you control.
• Tap target permanent an opponent controls.

Terastodon

When this creature enters, you may destroy up to three target noncreature permanents. For each permanent put into a graveyard this way, its controller creates a 3/3 green Elephant creature token.

Teardrop Kami

Sacrifice this creature: You may tap or untap target creature.

Llanowar Elves

Body Double

You may have this creature enter as a copy of any creature card in a graveyard.

Eternal Witness

When this creature enters, you may return target card from your graveyard to your hand.

Guardian Project

Whenever a nontoken creature you control enters, if it doesn't have the same name as another creature you control or a creature card in your graveyard, draw a card.

Woodfall Primus

Trample
When this creature enters, destroy target noncreature permanent.
Persist (When this creature dies, if it had no -1/-1 counters on it, return it to the battlefield under its owner's control with a -1/-1 counter on it.)

Simic Ascendancy

{1}{G}{U}: Put a +1/+1 counter on target creature you control.
Whenever one or more +1/+1 counters are put on a creature you control, put that many growth counters on this enchantment.
At the beginning of your upkeep, if this enchantment has twenty or more growth counters on it, you win the game.

Clear the Mind

Target player shuffles their graveyard into their library.
Draw a card.

Quirion Ranger

Return a Forest you control to its owner's hand: Untap target creature. Activate only once each turn.

Glasspool Shore

Glasspool Mimic

You may have this creature enter as a copy of a creature you control, except it's a Shapeshifter Rogue in addition to its other types.

Glasspool Mimic // Glasspool Shore

Liege of the Tangle

Trample
Whenever this creature deals combat damage to a player, you may choose any number of target lands you control and put an awakening counter on each of them. Each of those lands is an 8/8 green Elemental creature for as long as it has an awakening counter on it. They're still lands.

Exotic Orchard

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

Yavimaya Coast

{T}: Add {C}.
{T}: Add {G} or {U}. This land deals 1 damage to you.

Pongify

Destroy target creature. It can't be regenerated. Its controller creates a 3/3 green Ape creature token.

Patron of the Orochi

Snake offering (You may cast this spell any time you could cast an instant by sacrificing a Snake and paying the difference in mana costs between this and the sacrificed Snake. Mana cost includes color.)
{T}: Untap all Forests and all green creatures. Activate only once each turn.

Dreamdew Entrancer

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

Peregrine Drake

Flying
When this creature enters, untap up to five lands.

Great Oak Guardian

Flash (You may cast this spell any time you could cast an instant.)
Reach
When this creature enters, creatures target player controls get +2/+2 until end of turn. Untap them.

Evolutionary Leap

{G}, Sacrifice a creature: Reveal cards from the top of your library until you reveal a creature card. Put that card into your hand and the rest on the bottom of your library in a random order.

Pelt Collector

Whenever another creature you control enters or dies, if that creature's power is greater than this creature's, put a +1/+1 counter on this creature.
As long as this creature has three or more +1/+1 counters on it, it has trample.

Dryad Arbor

(This land isn't a spell, it's affected by summoning sickness, and it has "{T}: Add {G}.")

Saryth, the Viper's Fang

Other tapped creatures you control have deathtouch.
Other untapped creatures you control have hexproof.
{1}, {T}: Untap another target creature or land you control.

Evolving Wilds

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

Vizier of Tumbling Sands

{T}: Untap another target permanent.
Cycling {1}{U} ({1}{U}, Discard this card: Draw a card.)
When you cycle this card, untap target permanent.

Lonis, Cryptozoologist

Whenever another nontoken creature you control enters, investigate.
{T}, Sacrifice X Clues: Target opponent reveals the top X cards of their library. You may put a nonland permanent card with mana value X or less from among them onto the battlefield under your control. That player puts the rest on the bottom of their library in a random order.

Intruder Alarm

Creatures don't untap during their controllers' untap steps.
Whenever a creature enters, untap all creatures.

Command Tower

Retreat to Coralhelm

Landfall — Whenever a land you control enters, choose one —
• You may tap or untap target creature.
• Scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Deadeye Navigator

Soulbond (You may pair this creature with another unpaired creature when either enters. They remain paired for as long as you control both of them.)
As long as Deadeye Navigator is paired with another creature, each of those creatures has "{1}{U}: Exile this creature, then return it to the battlefield under your control."

Breaching Hippocamp

Flash (You may cast this spell any time you could cast an instant.)
When this creature enters, untap another target creature you control.

Elixir of Immortality

{2}, {T}: You gain 5 life. Shuffle this artifact and your graveyard into their owner's library.

Magic Damper

Target creature you control gets +1/+1 and gains hexproof until end of turn. Untap it.

Cerulean Wisps

Target creature becomes blue until end of turn. Untap that creature.
Draw a card.

Scryb Ranger

Flash
Flying, protection from blue
Return a Forest you control to its owner's hand: Untap target creature. Activate only once each turn.

Reclamation Sage

When this creature enters, you may destroy target artifact or enchantment.

Mystic Snake

Flash
When this creature enters, counter target spell.

Progenitor Mimic

You may have this creature enter as a copy of any creature on the battlefield, except it has "At the beginning of your upkeep, if this creature isn't a token, create a token that's a copy of this creature."

Terramorphic Expanse

Kiora, Behemoth Beckoner

Whenever a creature you control with power 4 or greater enters, draw a card.
−1: Untap target permanent.

Frilled Mystic

Flash
When this creature enters, you may counter target spell.

Moldgraf Monstrosity

Trample
When this creature dies, exile it, then return two creature cards at random from your graveyard to the battlefield.

Woodland Bellower

When this creature enters, you may search your library for a nonlegendary green creature card with mana value 3 or less, put it onto the battlefield, then shuffle.

Sharktocrab

{2}{G}{U}: Adapt 1. (If this creature has no +1/+1 counters on it, put a +1/+1 counter on it.)
Whenever one or more +1/+1 counters are put on this creature, tap target creature an opponent controls. That creature doesn't untap during its controller's next untap step.

Rapid Hybridization

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

Sin, Unending Cataclysm

Flying, trample
As Sin enters, remove all counters from any number of artifacts, creatures, and enchantments. Sin enters with X +1/+1 counters on it, where X is twice the number of counters removed this way.
When Sin dies, put its counters on target creature you control, then shuffle this card into its owner's library.

Timeless Witness

When this creature enters, return target card from your graveyard to your hand.
Eternalize {5}{G}{G} ({5}{G}{G}, Exile this card from your graveyard: Create a token that's a copy of it, except it's a 4/4 black Zombie Human Shaman with no mana cost. Eternalize only as a sorcery.)

Birthing Ritual

At the beginning of your end step, if you control a creature, look at the top seven cards of your library. Then you may sacrifice a creature. If you do, you may put a creature card with mana value X or less from among those cards onto the battlefield, where X is 1 plus the sacrificed creature's mana value. Put the rest on the bottom of your library in a random order.

Aggressive Mammoth

Trample (This creature can deal excess combat damage to the player or planeswalker it's attacking.)
Other creatures you control have trample.

Master Biomancer

Each other creature you control enters with a number of additional +1/+1 counters on it equal to this creature's power and as a Mutant in addition to its other types.

Weatherseed Treefolk

Trample
When this creature dies, return it to its owner's hand.

Piper's Melody

Shuffle any number of target creature cards from your graveyard into your library.

Phytotitan

When this creature dies, return it to the battlefield tapped under its owner's control at the beginning of their next upkeep.

Ancient Adamantoise

Vigilance, ward {3}
Damage isn't removed from this creature during cleanup steps.
All damage that would be dealt to you and other permanents you control is dealt to this creature instead.
When this creature dies, exile it and create ten tapped Treasure tokens.

Old-Growth Troll

Trample
When Old-Growth Troll dies, if it was a creature, return it to the battlefield. It's an Aura enchantment with enchant Forest you control and "Enchanted Forest has '{T}: Add {G}{G}' and '{1}, {T}, Sacrifice this land: Create a tapped 4/4 green Troll Warrior creature token with trample.'"

Beast Within

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

Gruff Triplets

Trample
When this creature enters, if it isn't a token, create two tokens that are copies of it.
When this creature dies, put a number of +1/+1 counters equal to its power on each creature you control named Gruff Triplets.

Shore Up

Target creature you control gets +1/+1 and gains hexproof until end of turn. Untap it. (It can't be the target of spells or abilities your opponents control.)

Giant Ankheg

Trample
Ward {2} (Whenever this creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays {2}.)
Other creatures you control have trample and ward {2}.

Prime Speaker Vannifar

{T}, Sacrifice another creature: Search your library for a creature card with mana value equal to 1 plus the sacrificed creature's mana value, put that card onto the battlefield, then shuffle. Activate only as a sorcery.

Island

Hydroid Krasis

When you cast this spell, you gain half X life and draw half X cards. Round down each time.
Flying, trample
This creature enters with X +1/+1 counters on it.

Ioreth of the Healing House

{T}: Untap another target permanent.
{T}: Untap two other target legendary creatures.

Pestermite

Flash
Flying
When this creature enters, you may tap or untap target permanent.

Kiora's Follower

Simic Growth Chamber

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

Hyrax Tower Scout

When this creature enters, untap target creature.

The Watcher in the Water

The Watcher in the Water enters tapped with nine stun counters on it. (If a permanent with a stun counter would become untapped, remove one from it instead.)
Whenever you draw a card during an opponent's turn, create a 1/1 blue Tentacle creature token.
Whenever a Tentacle you control dies, untap up to one target Kraken and put a stun counter on up to one target nonland permanent.

Memory's Journey

Target player shuffles up to three target cards from their graveyard into their library.
Flashback {G} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Bounding Krasis

Flash (You may cast this spell any time you could cast an instant.)
When this creature enters, you may tap or untap target creature.

Forensic Researcher

{T}: Untap another target permanent you control.
{T}, Collect evidence 3: Tap target creature you don't control. (To collect evidence 3, exile cards with total mana value 3 or greater from your graveyard.)

Repulsive Mutation

Put X +1/+1 counters on target creature you control. Then counter up to one target spell unless its controller pays mana equal to the greatest power among creatures you control.

Birthing Pod

({G/P} can be paid with either {G} or 2 life.)
{1}{G/P}, {T}, Sacrifice a creature: Search your library for a creature card with mana value equal to 1 plus the sacrificed creature's mana value, put that card onto the battlefield, then shuffle. Activate only as a sorcery.

Vitalize

Monstrosity of the Lake

When Monstrosity of the Lake enters, you may pay {5}. If you do, tap all creatures your opponents control, then put a stun counter on each of those creatures. (If a permanent with a stun counter would become untapped, remove one from it instead.)
Islandcycling {2} ({2}, Discard this card: Search your library for an Island card, reveal it, put it into your hand, then shuffle.)

Skyserpent Seeker

Flying, deathtouch
Exhaust — {4}: Reveal cards from the top of your library until you reveal two land cards. Put those land cards onto the battlefield tapped and the rest on the bottom of your library in a random order. Put a +1/+1 counter on this creature. (Activate each exhaust ability only once.)

Frost Titan

Whenever this creature becomes the target of a spell or ability an opponent controls, counter that spell or ability unless its controller pays {2}.
Whenever this creature enters or attacks, tap target permanent. It doesn't untap during its controller's next untap step.

Growth Spiral

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

Forest

Loaming Shaman

When this creature enters, target player shuffles any number of target cards from their graveyard into their library.

Vineglimmer Snarl

As this land enters, you may reveal a Forest or Island card from your hand. If you don't, this land enters tapped.
{T}: Add {G} or {U}.