Sawhorn Nemesis

As Sawhorn Nemesis enters, choose a player.
If a source would deal damage to the chosen player or a permanent they control, it deals double that damage instead.

Solemn Simulacrum

When Solemn Simulacrum enters, you may search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.
When Solemn Simulacrum dies, you may draw a card.

Big Score

As an additional cost to cast this spell, discard a card.
Draw two cards and create two Treasure tokens. (They're artifacts with "{T}, Sacrifice this artifact: Add one mana of any color.")

Isengard Unleashed

Damage can't be prevented this turn. If a source you control would deal damage this turn to an opponent or a permanent an opponent controls, it deals triple that damage instead.
Flashback {4}{R}{R}{R} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Lightning Bolt

Lightning Bolt deals 3 damage to any target.

Alena, Kessig Trapper

First strike
{T}: Add an amount of {R} equal to the greatest power among creatures you control that entered this turn.
Partner (You can have two commanders if both have partner.)

Koth, Fire of Resistance

+2: Search your library for a basic Mountain card, reveal it, put it into your hand, then shuffle.
−3: Koth, Fire of Resistance deals damage to target creature equal to the number of Mountains you control.
−7: You get an emblem with "Whenever a Mountain you control enters, this emblem deals 4 damage to any target."

Fiendish Duo

First strike
If a source would deal damage to an opponent, it deals double that damage to that player instead.

Runaway Steam-Kin

Whenever you cast a red spell, if Runaway Steam-Kin has fewer than three +1/+1 counters on it, put a +1/+1 counter on Runaway Steam-Kin.
Remove three +1/+1 counters from Runaway Steam-Kin: Add {R}{R}{R}.

Chandra's Ignition

Target creature you control deals damage equal to its power to each other creature and each opponent.

Carnelian Orb of Dragonkind

{T}: Add {R}. If that mana is spent on a Dragon creature spell, it gains haste until end of turn.

Irencrag Feat

Add seven {R}. You can cast only one more spell this turn.

Rush of Blood

Target creature gets +X/+0 until end of turn, where X is its power.

Quest for Pure Flame

Whenever a source you control deals damage to an opponent, you may put a quest counter on Quest for Pure Flame.
Remove four quest counters from Quest for Pure Flame and sacrifice it: If any source you control would deal damage to a permanent or player this turn, it deals double that damage to that permanent or player instead.

Wild Magic Surge

Destroy target permanent an opponent controls. Its controller reveals cards from the top of their library until they reveal a permanent card that shares a card type with that permanent. They put that card onto the battlefield and the rest on the bottom of their library in a random order.

Temur Battle Rage

Target creature gains double strike until end of turn.
Ferocious — That creature also gains trample until end of turn if you control a creature with power 4 or greater.

Glittering Stockpile

{T}: Add {R}. Put a stash counter on Glittering Stockpile.
{T}, Sacrifice Glittering Stockpile: Add X mana of any one color, where X is the number of stash counters on Glittering Stockpile.

Koth of the Hammer

+1: Untap target Mountain. It becomes a 4/4 red Elemental creature until end of turn. It's still a land.
−2: Add {R} for each Mountain you control.
−5: You get an emblem with "Mountains you control have '{T}: This land deals 1 damage to any target.'"

Inferno of the Star Mounts

This spell can't be countered.
Flying, haste
{R}: Inferno of the Star Mounts gets +1/+0 until end of turn. When its power becomes 20 this way, it deals 20 damage to any target.

Unexpected Windfall

Granite Grip

Enchant creature
Enchanted creature gets +1/+0 for each Mountain you control.

Curse of Bloodletting

Enchant player
If a source would deal damage to enchanted player, it deals double that damage to that player instead.

Claws of Valakut

Enchant creature
Enchanted creature gets +1/+0 for each Mountain you control and has first strike.

Tormenting Voice

As an additional cost to cast this spell, discard a card.
Draw two cards.

Neheb, the Eternal

Afflict 3 (Whenever this creature becomes blocked, defending player loses 3 life.)
At the beginning of each of your postcombat main phases, add {R} for each 1 life your opponents have lost this turn.

Faithless Looting

Draw two cards, then discard two cards.
Flashback {2}{R} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Abrade

Choose one —
• Abrade deals 3 damage to target creature.
• Destroy target artifact.

Iron Myr

The Reaver Cleaver

Equipped creature gets +1/+1 and has trample and "Whenever this creature deals combat damage to a player or planeswalker, create that many Treasure tokens."
Equip {3}

Gratuitous Violence

If a creature you control would deal damage to a permanent or player, it deals double that damage to that permanent or player instead.

Rogue's Passage

{T}: Add {C}.
{4}, {T}: Target creature can't be blocked this turn.

Crime Novelist

Whenever you sacrifice an artifact, put a +1/+1 counter on Crime Novelist and add {R}.

Arcane Signet

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

Cursed Mirror

{T}: Add {R}.
As Cursed Mirror enters, you may have it become a copy of any creature on the battlefield until end of turn, except it has haste.

Gavel of the Righteous

At the beginning of combat on your turn, put a charge counter on Gavel of the Righteous.
Equipped creature gets +1/+1 for each counter on Gavel of the Righteous.
As long as Gavel of the Righteous has four or more counters on it, equipped creature has double strike.
Equip—Pay {3} or remove a counter from Gavel of the Righteous.

Angrath's Marauders

If a source you control would deal damage to a permanent or player, it deals double that damage to that permanent or player instead.

Soul's Fire

Target creature you control deals damage equal to its power to any target.

Brass's Bounty

For each land you control, create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Sweeping Cleave

Target creature you control gains double strike until end of turn. (Then exile this card. You may cast the artifact later from exile.)

Two-Handed Axe

Whenever equipped creature attacks, double its power until end of turn.
Equip {1}{R}

Two-Handed Axe // Sweeping Cleave

Unleash Fury

Double the power of target creature until end of turn.

Sazacap's Brew

Gift a tapped Fish (You may promise an opponent a gift as you cast this spell. If you do, they create a tapped 1/1 blue Fish creature token before its other effects.)
As an additional cost to cast this spell, discard a card.
Target player draws two cards. If the gift was promised, target creature you control gets +2/+0 until end of turn.

Soulbright Flamekin

{2}: Target creature gains trample until end of turn. If this is the third time this ability has resolved this turn, you may add {R}{R}{R}{R}{R}{R}{R}{R}.

Blackblade Reforged

Equipped creature gets +1/+1 for each land you control.
Equip legendary creature {3}
Equip {7}

Diamond Pick-Axe

Indestructible (Effects that say "destroy" don't destroy this artifact.)
Equipped creature gets +1/+1 and has "Whenever this creature attacks, create a Treasure token." (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")
Equip {2}