Modern Horizons 3

Galvanic Discharge

Galvanic Discharge {R}

Instant
Choose target creature or planeswalker. You get {E}{E}{E}, then you may pay any amount of {E}. Galvanic Discharge deals that much damage to that permanent.
"Remember, if you find a rock making crackly noises, just put it back. Carefully."
—Bo, Great Desert prospector
Related card: Galvanic Discharge (Alchemy)
Ghostfire Slice

Ghostfire Slice {2}{R}

Instant
Devoid
This spell costs {2} less to cast if an opponent controls a multicolored permanent.
Ghostfire Slice deals 4 damage to any target.
Just because you can't see it doesn't mean it won't hurt.
Glimpse the Impossible

Glimpse the Impossible {2}{R}

Sorcery
Exile the top three cards of your library. You may play those cards this turn. At the beginning of the next end step, if any of those cards remain exiled, put them into your graveyard, then create a 0/1 colorless Eldrazi Spawn creature token for each card put into your graveyard this way. Those tokens have "Sacrifice this token: Add {C}."
Gisela beheld true divinity, and was humbled.
Infernal Captor

Infernal Captor {3}{R}

Creature - Devil Rogue
Exploit
When this creature exploits a creature, gain control of target artifact or creature until end of turn. Untap that permanent. It gains haste until end of turn.
Possession is nine-tenths of the law. His fist is the other tenth.
3/3
Inventor's Axe

Inventor's Axe {R}

Artifact - Equipment
Flash
When this Equipment enters, you get {E}{E}.
When this Equipment enters, attach it to target creature you control.
Equipped creature gets +2/+0.
Equip—Pay {E}{E}.
Mogg Mob

Mogg Mob {R}{R}{R}

Creature - Goblin
Sacrifice this creature: It deals 3 damage divided as you choose among one, two, or three targets.
There was absolutely nothing suspicious about three moggs carrying barrels of explosives—or so they told everyone who would listen.
3/3
Molten Gatekeeper

Molten Gatekeeper {2}{R}

Artifact Creature - Golem
Whenever another creature you control enters, this creature deals 1 damage to each opponent.
Unearth {R}
2/3
Party Thrasher

Party Thrasher {1}{R}

Creature - Lizard Wizard
Noncreature spells you cast from exile have convoke.
At the beginning of your first main phase, you may discard a card. If you do, exile the top two cards of your library, then choose one of them. You may play that card this turn.
1/4
Phyrexian Ironworks

Phyrexian Ironworks {2}{R}

Artifact
Whenever you attack, you get {E}.
{T}, Pay {E}{E}{E}: Create a 3/3 colorless Phyrexian Golem artifact creature token. Activate only as a sorcery.
"We have made a friend today."
—Slobad, Iron Goblin
Powerbalance

Powerbalance {R}{R}

Enchantment
Whenever an opponent casts a spell, you may reveal the top card of your library. If you do, you may cast that card without paying its mana cost if the two spells have the same mana value.
For every action, a reaction. For every force, a firestorm.
Ral and the Implicit Maze

Ral and the Implicit Maze {3}{R}{R}

Enchantment - Saga
I — This Saga deals 2 damage to each creature and planeswalker your opponents control.
II — You may discard a card. If you do, exile the top two cards of your library. You may play them until the end of your next turn.
III — Create a Spellgorger Weird token.
Reckless Pyrosurfer

Reckless Pyrosurfer {1}{R}

Creature - Human Scout
Haste
Landfall — Whenever a land you control enters, this creature gains battle cry until end of turn.
2/2
Reiterating Bolt

Reiterating Bolt {1}{R}

Sorcery
Replicate—Pay {E}{E}{E}.
Reiterating Bolt deals 3 damage to target creature or planeswalker.
"Eureka! Now to show those fools at the Academy how easily I can replicate these results!"
Sarpadian Simulacrum

Sarpadian Simulacrum {R}

Artifact Creature - Goblin
Haste
{3}{R}, Sacrifice this creature: It deals 4 damage to target creature.
Built to be super soldiers, the goblins preferred just being super destructive.
1/1
Siege Smash

Siege Smash {1}{R}

Instant
Split second
Choose one —
• Destroy target artifact.
• Target creature gets +3/+2 and gains trample until end of turn.
Skittering Precursor

Skittering Precursor {2}{R}

Creature - Eldrazi Drone
Devoid
Menace
Whenever you sacrifice a nontoken permanent, create a 0/1 colorless Eldrazi Spawn creature token with "Sacrifice this token: Add {C}."
It pushes ahead, eliminating lookouts and tactically sowing spawn.
3/3
Skoa, Embermage

Skoa, Embermage {4}{R}{R}

Legendary Creature - Goblin Wizard
When Skoa enters, it deals 4 damage to any target.
Grandeur — Discard another card named Skoa, Embermage, Sacrifice two Mountains: Skoa deals 4 damage to any target.
"I need kindling. You'll do nicely."
4/4
Related card: Sacrifice
Smelted Chargebug

Smelted Chargebug {1}{R}

Artifact Creature - Insect
Menace
When this creature enters, you get {E}{E}.
Whenever this creature attacks, you may pay {E}. If you do, another target attacking creature gets +1/+0 and gains menace until end of turn.
1/3
Spawn-Gang Commander

Spawn-Gang Commander {3}{R}{R}

Creature - Eldrazi Goblin
Devoid
When you cast this spell, create three 0/1 colorless Eldrazi Spawn creature tokens with "Sacrifice this token: Add {C}."
{1}{C}, Sacrifice an Eldrazi: This creature deals 2 damage to any target.
2/2
Thriving Skyclaw

Thriving Skyclaw {2}{R}{R}

Creature - Cat Dragon
Flying
When this creature enters, you get {E}{E}{E}.
Whenever this creature attacks, you may pay {E}{E}{E}. If you do, put a +1/+1 counter on it.
As wild as unbound aether, and just as dangerous.
3/2
Unstable Amulet

Unstable Amulet {1}{R}

Artifact
When this artifact enters, you get {E}{E}.
Whenever you cast a spell from anywhere other than your hand, this artifact deals 1 damage to each opponent.
{T}, Pay {E}{E}: Exile the top card of your library. You may play it until you exile another card with this artifact.
Voidpouncer

Voidpouncer {1}{R}

Creature - Eldrazi
Devoid
Kicker {2}{C}
If this creature was kicked, it enters with two +1/+1 counters and a trample counter on it and with haste.
3/1
Wheel of Potential

Wheel of Potential {2}{R}

Sorcery
You get {E}{E}{E}, then you may pay any amount of {E}.
Each player may exile their hand and draw a number of cards equal to the amount of {E} paid this way. If seven or more {E} was paid this way, you may play cards you own exiled this way until the end of your next turn.
The wheel only has one sure output: chaos.
Basking Broodscale

Basking Broodscale {1}{G}

Creature - Eldrazi Lizard
Devoid
{1}{G}: Adapt 1.
Whenever one or more +1/+1 counters are put on this creature, you may create a 0/1 colorless Eldrazi Spawn creature token with "Sacrifice this token: Add {C}."
2/2
Birthing Ritual

Birthing Ritual {1}{G}

Enchantment
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.