Boil

Paragon of Fierce Defiance

Other red creatures you control get +1/+1.
{R}, {T}: Another target red creature you control gains haste until end of turn. (It can attack and {T} this turn.)

Warchief Giant

Haste
Myriad (Whenever this creature attacks, for each opponent other than defending player, you may create a token copy that's tapped and attacking that player or a planeswalker they control. Exile the tokens at end of combat.)

Ghitu Encampment

This land enters tapped.
{T}: Add {R}.
{1}{R}: This land becomes a 2/1 red Warrior creature with first strike until end of turn. It's still a land. (It deals combat damage before creatures without first strike.)

Impetuous Protege

Partner with Proud Mentor (When this creature enters, target player may put Proud Mentor into their hand from their library, then shuffle.)
Whenever this creature attacks, it gets +X/+0 until end of turn, where X is the greatest power among tapped creatures your opponents control.

Falkenrath Marauders

Flying
Haste (This creature can attack and {T} as soon as it comes under your control.)
Whenever this creature deals combat damage to a player, put two +1/+1 counters on it.

Pyroclasm

Pyroclasm deals 2 damage to each creature.

Brighthearth Banneret

Elemental spells and Warrior spells you cast cost {1} less to cast.
Reinforce 1—{1}{R} ({1}{R}, Discard this card: Put a +1/+1 counter on target creature.)

Flamerush Rider

Whenever this creature attacks, create a token that's a copy of another target attacking creature and that's tapped and attacking. Exile the token at end of combat.
Dash {2}{R}{R} (You may cast this spell for its dash cost. If you do, it gains haste, and it's returned from the battlefield to its owner's hand at the beginning of the next end step.)

Onslaught

Whenever you cast a creature spell, tap target creature.

Hamletback Goliath

Whenever another creature enters, you may put X +1/+1 counters on this creature, where X is that creature's power.

Mizzium Mortars

Mizzium Mortars deals 4 damage to target creature you don't control.
Overload {3}{R}{R}{R} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Neheb, Dreadhorde Champion

Trample
Whenever Neheb deals combat damage to a player or planeswalker, you may discard any number of cards. If you do, draw that many cards and add that much {R}. Until end of turn, you don't lose this mana as steps and phases end.

Tail Slash

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

Total War

Whenever a player attacks with one or more creatures, destroy all untapped non-Wall creatures that player controls that didn't attack, except for creatures the player hasn't controlled continuously since the beginning of the turn.

Inner-Flame Igniter

{2}{R}: Creatures you control get +1/+0 until end of turn. If this is the third time this ability has resolved this turn, creatures you control gain first strike until end of turn.

Fire-Belly Changeling

Changeling (This card is every creature type.)
{R}: This creature gets +1/+0 until end of turn. Activate no more than twice each turn.

Flamekin Brawler

{R}: This creature gets +1/+0 until end of turn.

Pyre Charger

Haste
{R}: This creature gets +1/+0 until end of turn.

Bloodmark Mentor

Red creatures you control have first strike.

Uphill Battle

Creatures played by your opponents enter tapped.

Mountain

Mob Mentality

Enchant creature
Enchanted creature has trample.
Whenever all non-Wall creatures you control attack, enchanted creature gets +X/+0 until end of turn, where X is the number of attacking creatures.

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}.

Rabble-Rouser

Bloodthirst 1 (If an opponent was dealt damage this turn, this creature enters with a +1/+1 counter on it.)
{R}, {T}: Attacking creatures get +X/+0 until end of turn, where X is this creature's power.

Wake of Destruction

Destroy target land and all other lands with the same name as that land.

Encroaching Wastes

{T}: Add {C}.
{4}, {T}, Sacrifice this land: Destroy target nonbasic land.

Ceaseless Searblades

Whenever you activate an ability of an Elemental, this creature gets +1/+0 until end of turn.

Flaring Flame-Kin

As long as this creature is enchanted, it gets +2/+2, has trample, and has "{R}: This creature gets +1/+0 until end of turn."

Vengeful Firebrand

This creature has haste as long as a Warrior card is in your graveyard.
{R}: This creature gets +1/+0 until end of turn.

Flamekin Bladewhirl

As an additional cost to cast this spell, reveal an Elemental card from your hand or pay {3}.

Breaking Point

Any player may have Breaking Point deal 6 damage to them. If no one does, destroy all creatures. Creatures destroyed this way can't be regenerated.

War-Spike Changeling

Changeling (This card is every creature type.)
{R}: This creature gains first strike until end of turn.

Meteor Blast

Meteor Blast deals 4 damage to each of X targets.

Flame Wave

Flame Wave deals 4 damage to target player or planeswalker and each creature that player or that planeswalker's controller controls.

Lava Flow

Scent of Cinder

Reveal any number of red cards in your hand. Scent of Cinder deals X damage to any target, where X is the number of cards revealed this way.

Fall of the Hammer

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

Boldwyr Intimidator

Cowards can't block Warriors.
{R}: Target creature becomes a Coward until end of turn.
{2}{R}: Target creature becomes a Warrior until end of turn.

Myriad Landscape

This land enters tapped.
{T}: Add {C}.
{2}, {T}, Sacrifice this land: Search your library for up to two basic land cards that share a land type, put them onto the battlefield tapped, then shuffle.

Ferocity of the Wilds

Attacking non-Human creatures you control get +1/+0 and have trample.

Heartlash Cinder

Haste
Chroma — When this creature enters, it gets +X/+0 until end of turn, where X is the number of red mana symbols in the mana costs of permanents you control.

Archetype of Aggression

Creatures you control have trample.
Creatures your opponents control lose trample and can't have or gain trample.

Flame Slash

Flame Slash deals 4 damage to target creature.

Academy Raider

Intimidate (This creature can't be blocked except by artifact creatures and/or creatures that share a color with it.)
Whenever this creature deals combat damage to a player, you may discard a card. If you do, draw a card.

Lovisa Coldeyes

Each creature that's a Barbarian, a Warrior, or a Berserker gets +2/+2 and has haste.

Iron Myr

Seething Pathblazer

Sacrifice an Elemental: This creature gets +2/+0 and gains first strike until end of turn.

Earthquake

Earthquake deals X damage to each creature without flying and each player.

Smoldering Spires

This land enters tapped.
When this land enters, target creature can't block this turn.
{T}: Add {R}.

Castle Embereth

This land enters tapped unless you control a Mountain.
{T}: Add {R}.
{1}{R}{R}, {T}: Creatures you control get +1/+0 until end of turn.

Okaun, Eye of Chaos

Partner with Zndrsplt, Eye of Wisdom (When this creature enters, target player may put Zndrsplt into their hand from their library, then shuffle.)
At the beginning of combat on your turn, flip a coin until you lose a flip.
Whenever a player wins a coin flip, double Okaun's power and toughness until end of turn.

Nova Chaser

Trample
Champion an Elemental (When this enters, sacrifice it unless you exile another Elemental you control. When this leaves the battlefield, that card returns to the battlefield.)

Smoldering Crater

This land enters tapped.
{T}: Add {R}.
Cycling {2} ({2}, Discard this card: Draw a card.)

Spinerock Knoll

Hideaway 4 (When this land enters, look at the top four cards of your library, exile one face down, then put the rest on the bottom in a random order.)
This land enters tapped.
{T}: Add {R}.
{R}, {T}: You may play the exiled card without paying its mana cost if an opponent was dealt 7 or more damage this turn.