Cleon, Merry Champion

Double strike
Heroic — Whenever you cast a spell that targets Cleon, exile the top card of your library. You may play that card until the end of your next turn.

Mirrorwing Dragon

Flying
Whenever a player casts an instant or sorcery spell that targets only Mirrorwing Dragon, that player copies that spell for each other creature they control that the spell could target. Each copy targets a different one of those creatures.

Wavecrash Triton

Heroic — Whenever you cast a spell that targets Wavecrash Triton, tap target creature an opponent controls. That creature doesn't untap during its controller's next untap step.

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.)

Vesuvan Duplimancy

Whenever you cast a spell that targets only a single artifact or creature you control, create a token that's a copy of that artifact or creature, except it's not legendary.

Chorus of the Tides

Flying
Heroic — Whenever you cast a spell that targets Chorus of the Tides, scry 1. (To scry 1, look at the top card of your library, then you may put that card on the bottom.)

Staunch-Hearted Warrior

Heroic — Whenever you cast a spell that targets Staunch-Hearted Warrior, put two +1/+1 counters on Staunch-Hearted Warrior.

Akroan Conscriptor

Heroic — Whenever you cast a spell that targets Akroan Conscriptor, gain control of another target creature until end of turn. Untap that creature. It gains haste until end of turn.

Labyrinth Champion

Heroic — Whenever you cast a spell that targets Labyrinth Champion, Labyrinth Champion deals 2 damage to any target.

Verdant Rebirth

Until end of turn, target creature gains "When this creature dies, return it to its owner's hand."
Draw a card.

Replicate

Create a token that's a copy of target creature you control.

Repudiate

Counter target activated or triggered ability. (Mana abilities can't be targeted.)

Repudiate // Replicate

Overprotect

Target creature you control gets +3/+3 and gains trample, hexproof, and indestructible until end of turn.

Mnemonic Nexus

Each player shuffles their graveyard into their library.

Setessan Oathsworn

Heroic — Whenever you cast a spell that targets Setessan Oathsworn, put two +1/+1 counters on Setessan Oathsworn.

Overrun

Creatures you control get +3/+3 and gain trample until end of turn. (Each of those creatures can deal excess combat damage to the player or planeswalker it's attacking.)

Irenicus's Vile Duplication

Create a token that's a copy of target creature you control, except the token has flying and it isn't legendary.

Followed Footsteps

Enchant creature
At the beginning of your upkeep, create a token that's a copy of enchanted creature.

Rosnakht, Heir of Rohgahh

Battle cry (Whenever this creature attacks, each other attacking creature gets +1/+0 until end of turn.)
Heroic — Whenever you cast a spell that targets Rosnakht, Heir of Rohgahh, create a 0/1 red Kobold creature token named Kobolds of Kher Keep.

Enter the Enigma

Target creature can't be blocked this turn.
Draw a card.

Expedite

Target creature gains haste until end of turn.
Draw a card.

Endless Evil

Enchant creature you control
At the beginning of your upkeep, create a token that's a copy of enchanted creature, except the token is 1/1.
When enchanted creature dies, if that creature was a Horror, return Endless Evil to its owner's hand.

Raking Claws

Target creature gains double strike until end of turn.
Cycling {2} ({2}, Discard this card: Draw a card.)

Frontline Heroism

When Frontline Heroism enters, create a 1/1 red Soldier creature token with haste.
Whenever you cast a spell that targets only a single creature you control, create a 1/1 red Soldier creature token with haste, then copy that spell. The copy targets that token.

Gaea's Gift

Put a +1/+1 counter on target creature you control. It gains reach, trample, hexproof, and indestructible until end of turn. (It can't be the target of spells or abilities your opponents control. Damage and effects that say "destroy" don't destroy it.)

Kalamax, the Stormsire

Whenever you cast your first instant spell each turn, if Kalamax, the Stormsire is tapped, copy that spell. You may choose new targets for the copy.
Whenever you copy an instant spell, put a +1/+1 counter on Kalamax.

Tel-Jilad Defiance

Target creature gains protection from artifacts until end of turn.
Draw a card.

Accelerate

Akroan Crusader

Heroic — Whenever you cast a spell that targets Akroan Crusader, create a 1/1 red Soldier creature token with haste. (It can attack and {T} as soon as it comes under your control.)

Refocus

Quickchange

Target creature becomes the color or colors of your choice until end of turn.
Draw a card.

Cytoshape

Choose a nonlegendary creature on the battlefield. Target creature becomes a copy of that creature until end of turn.

Mirage Mockery

Choose one —
• Create a token that's a copy of target artifact creature you control.
• Create a token that's a copy of target nonartifact creature you control.
Entwine {2}{U} (Choose both if you pay the entwine cost.)

Cloak of Feathers

Target creature gains flying until end of turn.
Draw a card.

Learn from the Past

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

Fleeting Reflection

Target creature you control gains hexproof until end of turn. Untap that creature. Until end of turn, it becomes a copy of up to one other target creature.

War-Wing Siren

Flying
Heroic — Whenever you cast a spell that targets War-Wing Siren, put a +1/+1 counter on War-Wing Siren.

Battlefield Thaumaturge

Each instant and sorcery spell you cast costs {1} less to cast for each creature it targets.
Heroic — Whenever you cast a spell that targets Battlefield Thaumaturge, Battlefield Thaumaturge gains hexproof until end of turn.

Aggressive Urge

Target creature gets +1/+1 until end of turn.
Draw a card.

Leap

Druid's Deliverance

Prevent all combat damage that would be dealt to you this turn. Populate. (Create a token that's a copy of a creature token you control.)

Triton Fortune Hunter

Heroic — Whenever you cast a spell that targets Triton Fortune Hunter, draw a card.

Sage of Hours

Heroic — Whenever you cast a spell that targets Sage of Hours, put a +1/+1 counter on it.
Remove all +1/+1 counters from Sage of Hours: For each five counters removed this way, take an extra turn after this one.

Might of the Meek

Target creature gains trample until end of turn. It also gets +1/+0 until end of turn if you control a Mouse.
Draw a card.

Collective Resistance

Escalate {G} (Pay this cost for each mode chosen beyond the first.)
Choose one or more —
• Destroy target artifact.
• Destroy target enchantment.
• Target creature gains hexproof and indestructible until end of turn.

Viridescent Wisps

Target creature becomes green and gets +1/+0 until end of turn.
Draw a card.

Charge Through

Target creature gains trample until end of turn.
Draw a card.

Overwhelming Stampede

Until end of turn, creatures you control gain trample and get +X/+X, where X is the greatest power among creatures you control.

Slip Through Space

Devoid (This card has no color.)
Target creature can't be blocked this turn.
Draw a card.

Forest

Chaos Warp

The owner of target permanent shuffles it into their library, then reveals the top card of their library. If it's a permanent card, they put it onto the battlefield.

Akroan Line Breaker

Heroic — Whenever you cast a spell that targets Akroan Line Breaker, Akroan Line Breaker gets +2/+0 and gains intimidate until end of turn. (It can't be blocked except by artifact creatures and/or creatures that share a color with it.)

Fated Infatuation

Create a token that's a copy of target creature you control. If it's your turn, scry 2.

Mountain

Cerulean Wisps

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

Zhalfirin Shapecraft

Target creature has base power and toughness 4/3 until end of turn.
Draw a card.

Fists of Flame

Draw a card. Until end of turn, target creature gains trample and gets +1/+0 for each card you've drawn this turn. (A creature with trample can deal excess combat damage to the player or planeswalker it's attacking.)

Artisan of Forms

Heroic — Whenever you cast a spell that targets Artisan of Forms, you may have Artisan of Forms become a copy of target creature, except it has this ability.

Dive Down

Target creature you control gets +0/+3 and gains hexproof until end of turn. (It can't be the target of spells or abilities your opponents control.)

Island

Mizzium Skin

Target creature you control gets +0/+1 and gains hexproof until end of turn.
Overload {1}{U} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Counterspell

Cackling Counterpart

Create a token that's a copy of target creature you control.
Flashback {5}{U}{U} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Shadow Rift

Target creature gains shadow until end of turn. (It can block or be blocked by only creatures with shadow.)
Draw a card.

Arcane Denial

Counter target spell. Its controller may draw up to two cards at the beginning of the next turn's upkeep.
You draw a card at the beginning of the next turn's upkeep.

Zada, Hedron Grinder

Whenever you cast an instant or sorcery spell that targets only Zada, Hedron Grinder, copy that spell for each other creature you control that the spell could target. Each copy targets a different one of those creatures.

Double Major

Copy target creature spell you control, except it isn't legendary if the spell is legendary. (A copy of a creature spell becomes a token.)

Hero of Leina Tower

Heroic — Whenever you cast a spell that targets Hero of Leina Tower, you may pay {X}. If you do, put X +1/+1 counters on Hero of Leina Tower.

Negate

Crimson Wisps

Target creature becomes red and gains haste until end of turn. (It can attack and {T} this turn.)
Draw a card.

Arena Athlete

Heroic — Whenever you cast a spell that targets Arena Athlete, target creature an opponent controls can't block this turn.

Poison the Blade

Target creature gains deathtouch until end of turn.
Draw a card.

Satyr Hoplite

Heroic — Whenever you cast a spell that targets Satyr Hoplite, put a +1/+1 counter on Satyr Hoplite.