Spawn of Thraxes

Flying
When this creature enters, it deals damage to any target equal to the number of Mountains you control.

Diamond Knight

Vigilance (Attacking doesn't cause this creature to tap.)
As this creature enters, choose a color.
Whenever you cast a spell of the chosen color, put a +1/+1 counter on this creature.

Pursue Glory

Attacking creatures get +2/+0 until end of turn.
Cycling {2} ({2}, Discard this card: Draw a card.)

Swashbuckling

Enchant creature
Enchanted creature gets +2/+2 and has haste.

Terror of Mount Velus

Flying
Double strike (This creature deals both first-strike and regular combat damage.)
When this creature enters, creatures you control gain double strike until end of turn.

Sun-Crowned Hunters

Enrage — Whenever this creature is dealt damage, it deals 3 damage to target opponent or planeswalker.

Archwing Dragon

Flying, haste
At the beginning of the end step, return this creature to its owner's hand.

Shivan Dragon

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

Tyrant of Valakut

Surge {3}{R}{R} (You may cast this spell for its surge cost if you or a teammate has cast another spell this turn.)
Flying
When this creature enters, if its surge cost was paid, it deals 3 damage to any target.

Skyscanner

Flying
When this creature enters, draw a card.

Hoard-Smelter Dragon

Flying
{3}{R}: Destroy target artifact. This creature gets +X/+0 until end of turn, where X is that artifact's mana value.

Scalding Cauldron

{3}, {T}, Sacrifice this artifact: It deals 3 damage to target creature.

Inescapable Brute

Wither (This deals damage to creatures in the form of -1/-1 counters.)
This creature must be blocked if able.

Mutiny

Target creature an opponent controls deals damage equal to its power to another target creature that player controls.

Unknown Shores

{T}: Add {C}.
{1}, {T}: Add one mana of any color.

Jaya, Venerated Firemage

If another red source you control would deal damage to a permanent or player, it deals that much damage plus 1 to that permanent or player instead.
−2: Jaya deals 2 damage to any target.

Dreamstone Hedron

{T}: Add {C}{C}{C}.
{3}, {T}, Sacrifice this artifact: Draw three cards.

Sarkhan the Masterless

Whenever a creature attacks you or a planeswalker you control, each Dragon you control deals 1 damage to that creature.
+1: Until end of turn, each planeswalker you control becomes a 4/4 red Dragon creature and gains flying.
−3: Create a 4/4 red Dragon creature token with flying.

Universal Automaton

Changeling (This card is every creature type.)

Steel Hellkite

Flying
{2}: This creature gets +1/+0 until end of turn.
{X}: Destroy each nonland permanent with mana value X whose controller was dealt combat damage by this creature this turn. Activate only once each turn.

Nest Robber

Shock

Luxa River Shrine

{1}, {T}: You gain 1 life. Put a brick counter on this artifact.
{T}: You gain 2 life. Activate only if there are three or more brick counters on this artifact.

Puncturing Blow

Puncturing Blow deals 5 damage to target creature. If that creature would die this turn, exile it instead.

Drakuseth, Maw of Flames

Flying
Whenever Drakuseth attacks, it deals 4 damage to any target and 3 damage to each of up to two other targets.

Burning-Tree Vandal

Riot (This creature enters with your choice of a +1/+1 counter or haste.)
Whenever this creature attacks, you may discard a card. If you do, draw a card.

Thunderous Might

Enchant creature
Whenever enchanted creature attacks, it gets +X/+0 until end of turn, where X is your devotion to red. (Each {R} in the mana costs of permanents you control counts toward your devotion to red.)

Shatter

Ryusei, the Falling Star

Flying
When Ryusei dies, it deals 5 damage to each creature without flying.

Screaming Shield

Equipped creature gets +0/+3 and has "{2}, {T}: Target player mills three cards."
Equip {3} ({3}: Attach to target creature you control. Equip only as a sorcery.)

Verix Bladewing

Kicker {3} (You may pay an additional {3} as you cast this spell.)
Flying
When Verix enters, if it was kicked, create Karox Bladewing, a legendary 4/4 red Dragon creature token with flying.

Fireshrieker

Equipped creature has double strike. (It deals both first-strike and regular combat damage.)
Equip {2} ({2}: Attach to target creature you control. Equip only as a sorcery.)

Dragon Hatchling

Spinning Wheel

{T}: Add one mana of any color.
{5}, {T}: Tap target creature.

Street Spasm

Street Spasm deals X damage to target creature without flying you don't control.
Overload {X}{X}{R}{R} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Utvara Hellkite

Flying
Whenever a Dragon you control attacks, create a 6/6 red Dragon creature token with flying.

Fling

As an additional cost to cast this spell, sacrifice a creature.
Fling deals damage equal to the sacrificed creature's power to any target.

Infuriate

Target creature gets +3/+2 until end of turn.

Akoum Hellkite

Flying
Landfall — Whenever a land you control enters, this creature deals 1 damage to any target. If that land is a Mountain, this creature deals 2 damage instead.

God-Pharaoh's Statue

Spells your opponents cast cost {2} more to cast.
At the beginning of your end step, each opponent loses 1 life.

Frilled Deathspitter

Enrage — Whenever this creature is dealt damage, it deals 2 damage to target opponent or planeswalker.

Sparkmage's Gambit

Sparkmage's Gambit deals 1 damage to each of up to two target creatures. Those creatures can't block this turn.

Flameblast Dragon

Flying
Whenever this creature attacks, you may pay {X}{R}. If you do, it deals X damage to any target.

Traveler's Amulet

{1}, Sacrifice this artifact: Search your library for a basic land card, reveal it, put it into your hand, then shuffle.

Demanding Dragon

Flying
When this creature enters, it deals 5 damage to target opponent unless that player sacrifices a creature of their choice.

Skyline Despot

Flying
When this creature enters, you become the monarch.
At the beginning of your upkeep, if you're the monarch, create a 5/5 red Dragon creature token with flying.

Fiery Finish

Fiery Finish deals 7 damage to target creature.

Hellkite Charger

Flying, haste
Whenever this creature attacks, you may pay {5}{R}{R}. If you do, untap all attacking creatures and after this phase, there is an additional combat phase.

Cosmotronic Wave

Cosmotronic Wave deals 1 damage to each creature your opponents control. Creatures your opponents control can't block this turn.

Sigil of Valor

Whenever equipped creature attacks alone, it gets +1/+1 until end of turn for each other creature you control.
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Insolent Neonate

Menace (This creature can't be blocked except by two or more creatures.)
Discard a card, Sacrifice this creature: Draw a card.

Ore-Scale Guardian

This spell costs {1} less to cast for each land card in your graveyard.
Flying, haste

Dragon Egg

Defender
When this creature dies, create a 2/2 red Dragon creature token with flying and "{R}: This token gets +1/+0 until end of turn."

Senseless Rage

Enchant creature
Enchanted creature gets +2/+2.
Madness {1}{R} (If you discard this card, discard it into exile. When you do, cast it for its madness cost or put it into your graveyard.)

Tyrant's Familiar

Flying, haste
Lieutenant — As long as you control your commander, this creature gets +2/+2 and has "Whenever this creature attacks, it deals 7 damage to target creature defending player controls."

Dragon Mage

Flying
Whenever this creature deals combat damage to a player, each player discards their hand, then draws seven cards.

Spectral Searchlight

{T}: Choose a player. That player adds one mana of any color they choose.

Lathliss, Dragon Queen

Flying
Whenever another nontoken Dragon you control enters, create a 5/5 red Dragon creature token with flying.
{1}{R}: Dragons you control get +1/+0 until end of turn.

Scorchmark

Scorchmark deals 2 damage to target creature. If that creature would die this turn, exile it instead.

Anax, Hardened in the Forge

Anax's power is equal to your devotion to red. (Each {R} in the mana costs of permanents you control counts toward your devotion to red.)
Whenever Anax or another nontoken creature you control dies, create a 1/1 red Satyr creature token with "This token can't block." If the creature had power 4 or greater, create two of those tokens instead.

Millstone

Sparktongue Dragon

Flying
When this creature enters, you may pay {2}{R}. When you do, it deals 3 damage to any target.

Tectonic Rift

Destroy target land. Creatures without flying can't block this turn.

Warcry Phoenix

Flying, haste
Whenever you attack with three or more creatures, you may pay {2}{R}. If you do, return this card from your graveyard to the battlefield tapped and attacking.

Ring of Valkas

Equipped creature has haste. (It can attack and {T} no matter when it came under your control.)
At the beginning of your upkeep, put a +1/+1 counter on equipped creature if it's red.
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)