Thundering Mightmare

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 Thundering Mightmare is paired with another creature, each of those creatures has "Whenever an opponent casts a spell, put a +1/+1 counter on this creature."

Into the Roil

Kicker {1}{U} (You may pay an additional {1}{U} as you cast this spell.)
Return target nonland permanent to its owner's hand. If this spell was kicked, draw a card.

Ordeal of Nylea

Enchant creature
Whenever enchanted creature attacks, put a +1/+1 counter on it. Then if it has three or more +1/+1 counters on it, sacrifice this Aura.
When you sacrifice this Aura, search your library for up to two basic land cards, put them onto the battlefield tapped, then shuffle.

Hydra's Growth

Enchant creature
When Hydra's Growth enters, put a +1/+1 counter on enchanted creature.
At the beginning of your upkeep, double the number of +1/+1 counters on enchanted creature.

Saproling Migration

Kicker {4} (You may pay an additional {4} as you cast this spell.)
Create two 1/1 green Saproling creature tokens. If this spell was kicked, create four of those tokens instead.

Elfhame Druid

{T}: Add {G}.
{T}: Add {G}{G}. Spend this mana only to cast kicked spells.

Field Research

Kicker {2}{U} (You may pay an additional {2}{U} as you cast this spell.)
Draw two cards. If this spell was kicked, draw three cards instead.

Flux Channeler

Whenever you cast a noncreature spell, proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Invigorating Surge

Put a +1/+1 counter on target creature you control, then double the number of +1/+1 counters on that creature.

Primal Growth

Kicker—Sacrifice a creature. (You may sacrifice a creature in addition to any other costs as you cast this spell.)
Search your library for a basic land card, put that card onto the battlefield, then shuffle. If this spell was kicked, instead search your library for up to two basic land cards, put them onto the battlefield, then shuffle.

Shell Shield

Kicker {1} (You may pay an additional {1} as you cast this spell.)
Target creature you control gets +0/+3 until end of turn. If this spell was kicked, that creature also gains hexproof until end of turn. (It can't be the target of spells or abilities your opponents control.)

Volshe Tideturner

{T}: Add {U}. Spend this mana only to cast an instant or sorcery spell or a kicked spell.

Vastwood Surge

Kicker {4} (You may pay an additional {4} as you cast this spell.)
Search your library for up to two basic land cards, put them onto the battlefield tapped, then shuffle. If this spell was kicked, put two +1/+1 counters on each creature you control.

Rushing River

Kicker—Sacrifice a land. (You may sacrifice a land in addition to any other costs as you cast this spell.)
Return target nonland permanent to its owner's hand. If this spell was kicked, return another target nonland permanent to its owner's hand.

Kami of Whispered Hopes

If one or more +1/+1 counters would be put on a permanent you control, that many plus one +1/+1 counters are put on that permanent instead.
{T}: Add X mana of any one color, where X is Kami of Whispered Hopes's power.

Thieving Skydiver

Kicker {X}. X can't be 0. (You may pay an additional {X} as you cast this spell.)
Flying
When Thieving Skydiver enters, if it was kicked, gain control of target artifact with mana value X or less. If that artifact is an Equipment, attach it to Thieving Skydiver.

Jace, Mirror Mage

Kicker {2}
When Jace, Mirror Mage enters, if Jace was kicked, create a token that's a copy of Jace, Mirror Mage, except it's not legendary and its starting loyalty is 1.
+1: Scry 2.
0: Draw a card and reveal it. Remove a number of loyalty counters equal to that card's mana value from Jace, Mirror Mage.

Bubble Snare

Kicker {2}{U} (You may pay an additional {2}{U} as you cast this spell.)
Enchant creature
When Bubble Snare enters, if it was kicked, tap enchanted creature.
Enchanted creature doesn't untap during its controller's untap step.

Krosan Druid

Kicker {4}{G} (You may pay an additional {4}{G} as you cast this spell.)
When Krosan Druid enters, if it was kicked, you gain 10 life.

Reclaim the Wastes

Kicker {3} (You may pay an additional {3} as you cast this spell.)
Search your library for a basic land card, reveal it, put it into your hand, then shuffle. If this spell was kicked, search your library for two basic land cards instead of one.

Tribute to the World Tree

Whenever a creature you control enters, draw a card if its power is 3 or greater. Otherwise, put two +1/+1 counters on it.

Murasa Sproutling

Kicker {1}{G} (You may pay an additional {1}{G} as you cast this spell.)
When Murasa Sproutling enters, if it was kicked, return target card with a kicker ability from your graveyard to your hand.

Vorel of the Hull Clade

{G}{U}, {T}: Double the number of each kind of counter on target artifact, creature, or land.

Skyclave Relic

Kicker {3}
Indestructible
When Skyclave Relic enters, if it was kicked, create two tapped tokens that are copies of Skyclave Relic.
{T}: Add one mana of any color.

Mold Shambler

Kicker {1}{G} (You may pay an additional {1}{G} as you cast this spell.)
When Mold Shambler enters, if it was kicked, destroy target noncreature permanent.

Myriad Construct

Kicker {3}
If Myriad Construct was kicked, it enters with a +1/+1 counter on it for each nonbasic land your opponents control.
When Myriad Construct becomes the target of a spell, sacrifice it and create a number of 1/1 colorless Construct artifact creature tokens equal to its power.

Tazeem Roilmage

Kicker {4} (You may pay an additional {4} as you cast this spell.)
When Tazeem Roilmage enters, if it was kicked, return target instant or sorcery card from your graveyard to your hand.

Untamed Kavu

Kicker {3} (You may pay an additional {3} as you cast this spell.)
Vigilance, trample
If Untamed Kavu was kicked, it enters with three +1/+1 counters on it.

Throne of Makindi

{T}: Add {C}.
{1}, {T}: Put a charge counter on Throne of Makindi.
{T}, Remove a charge counter from Throne of Makindi: Add two mana of any one color. Spend this mana only to cast kicked spells.

Branching Evolution

If one or more +1/+1 counters would be put on a creature you control, twice that many +1/+1 counters are put on that creature instead.

Sphinx of Lost Truths

Kicker {1}{U} (You may pay an additional {1}{U} as you cast this spell.)
Flying
When Sphinx of Lost Truths enters, draw three cards. Then if it wasn't kicked, discard three cards.

Wild Onslaught

Kicker {4} (You may pay an additional {4} as you cast this spell.)
Put a +1/+1 counter on each creature you control. If this spell was kicked, put two +1/+1 counters on each creature you control instead.

Maddening Cacophony

Kicker {3}{U}
Each opponent mills eight cards. If this spell was kicked, instead each opponent mills half their library, rounded up.

Territorial Allosaurus

Kicker {2}{G} (You may pay an additional {2}{G} as you cast this spell.)
When Territorial Allosaurus enters, if it was kicked, it fights another target creature.

Wolfbriar Elemental

Multikicker {G} (You may pay an additional {G} any number of times as you cast this spell.)
When Wolfbriar Elemental enters, create a 2/2 green Wolf creature token for each time it was kicked.

Sea Gate Stormcaller

Kicker {4}{U}
When Sea Gate Stormcaller enters, copy the next instant or sorcery spell with mana value 2 or less you cast this turn when you cast it. If Sea Gate Stormcaller was kicked, copy that spell twice instead. You may choose new targets for the copies.

Merfolk Falconer

Flying
Whenever you cast a kicked spell, scry 2.

Forgotten Ancient

Whenever a player casts a spell, you may put a +1/+1 counter on Forgotten Ancient.
At the beginning of your upkeep, you may move any number of +1/+1 counters from Forgotten Ancient onto other creatures.

Grow from the Ashes

Kicker {2} (You may pay an additional {2} as you cast this spell.)
Search your library for a basic land card, put it onto the battlefield, then shuffle. If this spell was kicked, instead search your library for two basic land cards, put them onto the battlefield, then shuffle.

Twinning Staff

If you would copy a spell one or more times, instead copy it that many times plus an additional time. You may choose new targets for the additional copy.
{7}, {T}: Copy target instant or sorcery spell you control. You may choose new targets for the copy.

Spell Contortion

Multikicker {1}{U} (You may pay an additional {1}{U} any number of times as you cast this spell.)
Counter target spell unless its controller pays {2}. Draw a card for each time Spell Contortion was kicked.

Ozolith, the Shattered Spire

If one or more +1/+1 counters would be put on an artifact or creature you control, that many plus one +1/+1 counters are put on it instead.
{1}{G}, {T}: Put a +1/+1 counter on target artifact or creature you control. Activate only as a sorcery.
Cycling {2} ({2}, Discard this card: Draw a card.)

Rite of Replication

Kicker {5} (You may pay an additional {5} as you cast this spell.)
Create a token that's a copy of target creature. If this spell was kicked, create five of those tokens instead.

Gnarlid Colony

Kicker {2}{G} (You may pay an additional {2}{G} as you cast this spell.)
If this creature was kicked, it enters with two +1/+1 counters on it.
Each creature you control with a +1/+1 counter on it has trample. (It can deal excess combat damage to the player or planeswalker it's attacking.)

Vineshaper Prodigy

Kicker {1}{U} (You may pay an additional {1}{U} as you cast this spell.)
When Vineshaper Prodigy enters, if it was kicked, look at the top three cards of your library. Put one of them into your hand and the rest on the bottom of your library in any order.

Blink of an Eye

Cragplate Baloth

Kicker {2}{G}
This spell can't be countered.
Hexproof, haste
If Cragplate Baloth was kicked, it enters with four +1/+1 counters on it.

Lullmage's Familiar

{T}: Add {G} or {U}.
Whenever you cast a kicked spell, you gain 2 life.

Incubation Druid

{T}: Add one mana of any type that a land you control could produce. If Incubation Druid has a +1/+1 counter on it, add three mana of that type instead.
{3}{G}{G}: Adapt 3. (If this creature has no +1/+1 counters on it, put three +1/+1 counters on it.)

Inscription of Abundance

Kicker {2}{G}
Choose one. If this spell was kicked, choose any number instead.
• Put two +1/+1 counters on target creature.
• Target player gains X life, where X is the greatest power among creatures they control.
• Target creature you control fights target creature you don't control.

Strength of the Tajuru

Multikicker {1} (You may pay an additional {1} any number of times as you cast this spell.)
Choose target creature, then choose another target creature for each time this spell was kicked. Put X +1/+1 counters on each of them.

Roost of Drakes

Kicker {2}{U} (You may pay an additional {2}{U} as you cast this spell.)
When Roost of Drakes enters, if it was kicked, create a 2/2 blue Drake creature token with flying.
Whenever you cast a kicked spell, create a 2/2 blue Drake creature token with flying.

Hardened Scales

If one or more +1/+1 counters would be put on a creature you control, that many plus one +1/+1 counters are put on it instead.

Citanul Woodreaders

Kicker {2}{G} (You may pay an additional {2}{G} as you cast this spell.)
When Citanul Woodreaders enters, if it was kicked, draw two cards.

Joint Exploration

Kicker {G} (You may pay an additional {G} as you cast this spell.)
Scry 2, then draw a card. If this spell was kicked, you may put a land card from your hand onto the battlefield.

Evolution Sage

Landfall — Whenever a land you control enters, proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Visions of Dominance

Put a +1/+1 counter on target creature, then double the number of +1/+1 counters on it.
Flashback {8}{G}{G}. This spell costs {X} less to cast this way, where X is the greatest mana value of a commander you own on the battlefield or in the command zone. (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Vine Gecko

The first kicked spell you cast each turn costs {1} less to cast.
Whenever you cast a kicked spell, put a +1/+1 counter on Vine Gecko.

Coralhelm Chronicler

Whenever you cast a kicked spell, draw a card, then discard a card.
When Coralhelm Chronicler enters, look at the top five cards of your library. You may reveal a card with a kicker ability from among them and put it into your hand. Put the rest on the bottom of your library in a random order.

Hunting Wilds

Kicker {3}{G} (You may pay an additional {3}{G} as you cast this spell.)
Search your library for up to two Forest cards, put them onto the battlefield tapped, then shuffle.
If this spell was kicked, untap all Forests put onto the battlefield this way. They become 3/3 green creatures with haste that are still lands.

Saproling Infestation

Whenever a player kicks a spell, you create a 1/1 green Saproling creature token.

Cunning Geysermage

Kicker {2}{U} (You may pay an additional {2}{U} as you cast this spell.)
When Cunning Geysermage enters, if it was kicked, return up to one other target creature to its owner's hand.

Verazol, the Split Current

Verazol, the Split Current enters with a +1/+1 counter on it for each mana spent to cast it.
Whenever you cast a kicked spell, you may remove two +1/+1 counters from Verazol. If you do, copy that spell. You may choose new targets for the copy. (A copy of a permanent spell becomes a token.)

Elvish Hydromancer

Kicker {3}{U} (You may pay an additional {3}{U} as you cast this spell.)
When Elvish Hydromancer enters, if it was kicked, create a token that's a copy of target creature you control.

Ruinous Intrusion

Exile target artifact or enchantment. Put X +1/+1 counters on target creature you control, where X is the mana value of the permanent exiled this way.

Yavimaya Coast

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

Master Biomancer

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

Everflowing Chalice

Multikicker {2} (You may pay an additional {2} any number of times as you cast this spell.)
Everflowing Chalice enters with a charge counter on it for each time it was kicked.
{T}: Add {C} for each charge counter on Everflowing Chalice.