Dragon Whelp

Flying
{R}: Dragon Whelp gets +1/+0 until end of turn. If this ability has been activated four or more times this turn, sacrifice Dragon Whelp at the beginning of the next end step.

Island

Juvenile Mist Dragon

Flying
Confounding Clouds — When Juvenile Mist Dragon enters, for each opponent, tap up to one target creature that player controls. Each of those creatures doesn't untap during its controller's next untap step.

Ganax, Astral Hunter

Flying
Whenever Ganax, Astral Hunter or another Dragon you control enters, create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")
Choose a Background (You can have a Background as a second commander.)

Verix Bladewing

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

Thriving Bluff

Thriving Bluff enters tapped. As it enters, choose a color other than red.
{T}: Add {R} or one mana of the chosen color.

Charmed Sleep

Enchant creature
When Charmed Sleep enters, tap enchanted creature.
Enchanted creature doesn't untap during its controller's untap step.

Fire Diamond

Fire Diamond enters tapped.
{T}: Add {R}.

Backdraft Hellkite

Flying
Whenever Backdraft Hellkite attacks, each instant and sorcery card in your graveyard gains flashback until end of turn. The flashback cost is equal to its mana cost.

Nimbleclaw Adept

Bigby's Hand — {T}: Untap two other target permanents. Activate only as a sorcery and only once each turn.

Dragon Egg

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

Ojutai's Breath

Tap target creature. It doesn't untap during its controller's next untap step.
Rebound (If you cast this spell from your hand, exile it as it resolves. At the beginning of your next upkeep, you may cast this card from exile without paying its mana cost.)

Essence Scatter

Mountain

Sprite Dragon

Flying, haste
Whenever you cast a noncreature spell, put a +1/+1 counter on Sprite Dragon.

Draconic Intervention

As an additional cost to cast this spell, exile an instant or sorcery card from your graveyard.
Draconic Intervention deals X damage to each non-Dragon creature, where X is the exiled card's mana value. If a creature dealt damage this way would die this turn, exile it instead.
Exile Draconic Intervention.

Ore-Scale Guardian

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

Hoard-Smelter Dragon

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

Sparktongue Dragon

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

Blazing Volley

Blazing Volley deals 1 damage to each creature your opponents control.

Dormant Volcano

Dormant Volcano enters tapped.
When Dormant Volcano enters, sacrifice it unless you return an untapped Mountain you control to its owner's hand.
{T}: Add {C}{R}.

Ashmouth Dragon

Flying
Whenever you cast an instant or sorcery spell, Ashmouth Dragon deals 2 damage to any target.

Smoldering Egg

Defender
Whenever you cast an instant or sorcery spell, put a number of ember counters on Smoldering Egg equal to the amount of mana spent to cast that spell. Then if Smoldering Egg has seven or more ember counters on it, remove them and transform Smoldering Egg.

Smoldering Egg // Ashmouth Dragon

Negate

Dragon Turtle

Flash
Drag Below — When Dragon Turtle enters, tap it and up to one target creature an opponent controls. They don't untap during their controllers' next untap steps.

Blue Dragon

Flying
Lightning Breath — When Blue Dragon enters, until your next turn, target creature an opponent controls gets -3/-0, up to one other target creature gets -2/-0, and up to one other target creature gets -1/-0.

Stormwing Dragon

Flying, first strike
Megamorph {5}{R}{R} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its megamorph cost and put a +1/+1 counter on it.)
When Stormwing Dragon is turned face up, put a +1/+1 counter on each other Dragon creature you control.

Cunning Strike

Cunning Strike deals 2 damage to target creature and 2 damage to target player or planeswalker.
Draw a card.

Raking Claws

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

Volcanic Dragon

Dragon Mantle

Enchant creature
When Dragon Mantle enters, draw a card.
Enchanted creature has "{R}: This creature gets +1/+0 until end of turn."

Reckless Barbarian

Sacrifice Reckless Barbarian: Add {R}{R}.

Dragon Engine

{2}: Dragon Engine gets +1/+0 until end of turn.

Thriving Isle

Thriving Isle enters tapped. As it enters, choose a color other than blue.
{T}: Add {U} or one mana of the chosen color.

Sky Diamond

Swiftwater Cliffs

This land enters tapped.
When this land enters, you gain 1 life.
{T}: Add {U} or {R}.

Day of the Dragons

When Day of the Dragons enters, exile all creatures you control. Then create that many 5/5 red Dragon creature tokens with flying.
When Day of the Dragons leaves the battlefield, sacrifice all Dragons you control. Then return the exiled cards to the battlefield under your control.

Wind Drake

Draconic Roar

As an additional cost to cast this spell, you may reveal a Dragon card from your hand.
Draconic Roar deals 3 damage to target creature. If you revealed a Dragon card or controlled a Dragon as you cast this spell, Draconic Roar deals 3 damage to that creature's controller.