Forced Adaptation

Enchant creature
At the beginning of your upkeep, put a +1/+1 counter on enchanted creature.

Formless Nurturing

Manifest the top card of your library, then put a +1/+1 counter on it. (To manifest a card, put it onto the battlefield face down as a 2/2 creature. Turn it face up any time for its mana cost if it's a creature card.)

Thallid

At the beginning of your upkeep, put a spore counter on this creature.
Remove three spore counters from this creature: Create a 1/1 green Saproling creature token.

Whispersilk Cloak

Equipped creature can't be blocked and has shroud. (It can't be the target of spells or abilities.)
Equip {2}

Spike Drone

This creature enters with a +1/+1 counter on it.
{2}, Remove a +1/+1 counter from this creature: Put a +1/+1 counter on target creature.

Haunted Fengraf

{T}: Add {C}.
{3}, {T}, Sacrifice this land: Return a creature card at random from your graveyard to your hand.

New Horizons

Enchant land
When this Aura enters, put a +1/+1 counter on target creature you control.
Enchanted land has "{T}: Add two mana of any one color."

Fertilid

This creature enters with two +1/+1 counters on it.
{1}{G}, Remove a +1/+1 counter from this creature: Target player searches their library for a basic land card, puts it onto the battlefield tapped, then shuffles.

Scrounging Bandar

This creature enters with two +1/+1 counters on it.
At the beginning of your upkeep, you may move any number of +1/+1 counters from this creature onto another target creature.

Mowu, Loyal Companion

Vigilance, trample
If one or more +1/+1 counters would be put on Mowu, that many plus one +1/+1 counters are put on it instead.

Thorn Thallid

At the beginning of your upkeep, put a spore counter on this creature.
Remove three spore counters from this creature: It deals 1 damage to any target.

Ranger's Guile

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

Wickerbough Elder

This creature enters with a -1/-1 counter on it.
{G}, Remove a -1/-1 counter from this creature: Destroy target artifact or enchantment.

Drudge Beetle

Scavenge {5}{G} ({5}{G}, Exile this card from your graveyard: Put a number of +1/+1 counters equal to this card's power on target creature. Scavenge only as a sorcery.)

Courage in Crisis

Put a +1/+1 counter on target creature, then proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Withstand Death

Target creature gains indestructible until end of turn. (Damage and effects that say "destroy" don't destroy it. If its toughness is 0 or less, it's still put into its owner's graveyard.)

Ivy Lane Denizen

Whenever another green creature you control enters, put a +1/+1 counter on target creature.

Living Totem

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.)
When this creature enters, you may put a +1/+1 counter on another target creature.

Timberland Guide

When this creature enters, put a +1/+1 counter on target creature.

Quarry Hauler

When this creature enters, for each kind of counter on target permanent, put another counter of that kind on it or remove one from it.

Avoid Fate

Counter target instant or Aura spell that targets a permanent you control.

Thallid Devourer

At the beginning of your upkeep, put a spore counter on this creature.
Remove three spore counters from this creature: Create a 1/1 green Saproling creature token.
Sacrifice a Saproling: This creature gets +1/+2 until end of turn.

Satyr Grovedancer

Explorer's Scope

Whenever equipped creature attacks, look at the top card of your library. If it's a land card, you may put it onto the battlefield tapped.
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Soul's Might

Put X +1/+1 counters on target creature, where X is that creature's power.

Ferocity

Enchant creature
Whenever enchanted creature blocks or becomes blocked, you may put a +1/+1 counter on it.

Rancor

Enchant creature
Enchanted creature gets +2/+0 and has trample.
When this Aura is put into a graveyard from the battlefield, return it to its owner's hand.

Sporeback Troll

Graft 2 (This creature enters with two +1/+1 counters on it. Whenever another creature enters, you may move a +1/+1 counter from this creature onto it.)
{1}{G}: Regenerate target creature with a +1/+1 counter on it.

Fortitude

Enchant creature
Sacrifice a Forest: Regenerate enchanted creature.
When this Aura is put into a graveyard from the battlefield, return it to its owner's hand.

Longshot Squad

Outlast {1}{G} ({1}{G}, {T}: Put a +1/+1 counter on this creature. Outlast only as a sorcery.)
Each creature you control with a +1/+1 counter on it has reach. (A creature with reach can block creatures with flying.)

Kavu Primarch

Kicker {4} (You may pay an additional {4} as you cast this spell.)
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.)
If this creature was kicked, it enters with four +1/+1 counters on it.

Hunt the Weak

Put a +1/+1 counter on target creature you control. Then that creature fights target creature you don't control. (Each deals damage equal to its power to the other.)

Forest

Thrive

Put a +1/+1 counter on each of X target creatures.

Vitaspore Thallid

At the beginning of your upkeep, put a spore counter on this creature.
Remove three spore counters from this creature: Create a 1/1 green Saproling creature token.
Sacrifice a Saproling: Target creature gains haste until end of turn.

Khalni Heart Expedition

Landfall — Whenever a land you control enters, you may put a quest counter on this enchantment.
Remove three quest counters from this enchantment and sacrifice it: Search your library for up to two basic land cards, put them onto the battlefield tapped, then shuffle.

Pinion Feast

Destroy target creature with flying. Bolster 2. (Choose a creature with the least toughness among creatures you control and put two +1/+1 counters on it.)

Servant of the Scale

This creature enters with a +1/+1 counter on it.
When this creature dies, put X +1/+1 counters on target creature you control, where X is the number of +1/+1 counters on this creature.

Simic Initiate

Graft 1 (This creature enters with a +1/+1 counter on it. Whenever another creature enters, you may move a +1/+1 counter from this creature onto it.)

Forge of Heroes

{T}: Add {C}.
{T}: Choose target commander that entered this turn. Put a +1/+1 counter on it if it's a creature and a loyalty counter on it if it's a planeswalker.

Opal Palace

{T}: Add {C}.
{1}, {T}: Add one mana of any color in your commander's color identity. If you spend this mana to cast your commander, it enters with a number of additional +1/+1 counters on it equal to the number of times it's been cast from the command zone this game.

Crowned Ceratok

Trample
Each creature you control with a +1/+1 counter on it has trample.

Serpent Skin

Flash
Enchant creature
Enchanted creature gets +1/+1.
{G}: Regenerate enchanted creature.

Serrated Arrows

This artifact enters with three arrowhead counters on it.
At the beginning of your upkeep, if there are no arrowhead counters on this artifact, sacrifice it.
{T}, Remove an arrowhead counter from this artifact: Put a -1/-1 counter on target creature.

Titanic Brawl

This spell costs {1} less to cast if it targets a creature you control with a +1/+1 counter on it.
Target creature you control fights target creature you don't control. (Each deals damage equal to its power to the other.)

Rabid Bite

Target creature you control deals damage equal to its power to target creature you don't control.

Aquastrand Spider

Graft 2 (This creature enters with two +1/+1 counters on it. Whenever another creature enters, you may move a +1/+1 counter from this creature onto it.)
{G}: Target creature with a +1/+1 counter on it gains reach until end of turn. (It can block creatures with flying.)

Baloth Gorger

Kicker {4} (You may pay an additional {4} as you cast this spell.)
If this creature was kicked, it enters with three +1/+1 counters on it.

Spike Worker

This creature enters with two +1/+1 counters on it.
{2}, Remove a +1/+1 counter from this creature: Put a +1/+1 counter on target creature.

Predatory Hunger

Enchant creature
Whenever an opponent casts a creature spell, put a +1/+1 counter on enchanted creature.

Strider Harness

Equipped creature gets +1/+1 and has haste.
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Sparring Construct

When this creature dies, put a +1/+1 counter on target creature you control.

Tishana's Wayfinder

When this creature enters, it explores. (Reveal the top card of your library. Put that card into your hand if it's a land. Otherwise, put a +1/+1 counter on this creature, then put the card back or put it into your graveyard.)

Savage Thallid

At the beginning of your upkeep, put a spore counter on this creature.
Remove three spore counters from this creature: Create a 1/1 green Saproling creature token.
Sacrifice a Saproling: Regenerate target Fungus.

Ainok Guide

When this creature enters, choose one —
• Put a +1/+1 counter on this creature.
• Search your library for a basic land card, reveal it, then shuffle and put that card on top.

Broken Fall

Return this enchantment to its owner's hand: Regenerate target creature.

Ancient Animus

Put a +1/+1 counter on target creature you control if it's legendary. Then it fights target creature an opponent controls. (Each deals damage equal to its power to the other.)

Vorrac Battlehorns

Equipped creature has trample and can't be blocked by more than one creature.
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery. This card enters unattached and stays on the battlefield if the creature leaves.)

Jade Guardian

Hexproof (This creature can't be the target of spells or abilities your opponents control.)
When this creature enters, put a +1/+1 counter on target Merfolk you control.

Thallid Shell-Dweller

Defender
At the beginning of your upkeep, put a spore counter on this creature.
Remove three spore counters from this creature: Create a 1/1 green Saproling creature token.

Mortal's Resolve

Target creature gets +1/+1 and gains indestructible until end of turn. (Damage and effects that say "destroy" don't destroy it.)

Thallid Germinator

At the beginning of your upkeep, put a spore counter on this creature.
Remove three spore counters from this creature: Create a 1/1 green Saproling creature token.
Sacrifice a Saproling: Target creature gets +1/+1 until end of turn.

Pollenbright Druid

When this creature enters, choose one —
• Put a +1/+1 counter on target creature.
• Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Sporoloth Ancient

At the beginning of your upkeep, put a spore counter on this creature.
Creatures you control have "Remove two spore counters from this creature: Create a 1/1 green Saproling creature token."

Spike Colony

This creature enters with four +1/+1 counters on it.
{2}, Remove a +1/+1 counter from this creature: Put a +1/+1 counter on target creature.

Bond Beetle

Korozda Monitor

Trample
Scavenge {5}{G}{G} ({5}{G}{G}, Exile this card from your graveyard: Put a number of +1/+1 counters equal to this card's power on target creature. Scavenge only as a sorcery.)

Bladed Pinions

Equipped creature has flying and first strike.
Equip {2}

Sphere of the Suns

This artifact enters tapped and with three charge counters on it.
{T}, Remove a charge counter from this artifact: Add one mana of any color.