Renari, Merchant of Marvels

You may cast Dragon spells and artifact spells as though they had flash.
Choose a Background (You can have a Background as a second commander.)

Rampant Growth

Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Mountain

Zoological Study

Mill five cards, then return a creature card milled this way to your hand. (Then exile this card. You may cast the artifact later from exile.)

Monster Manual

{1}{G}, {T}: You may put a creature card from your hand onto the battlefield.

Monster Manual // Zoological Study

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.

Fallaji Dragon Engine

Prototype {2}{R} — 1/3 (You may cast this spell with different mana cost, color, and size. It keeps its abilities and types.)
Flying
{2}: This creature gets +1/+0 until end of turn.

Goblin Anarchomancer

Each spell you cast that's red or green costs {1} less to cast.

Crucible of the Spirit Dragon

{T}: Add {C}.
{1}, {T}: Put a storage counter on this land.
{T}, Remove X storage counters from this land: Add X mana in any combination of colors. Spend this mana only to cast Dragon spells or activate abilities of Dragons.

Dragonlord's Servant

Dragon spells you cast cost {1} less to cast.

Kodama's Reach

Search your library for up to two basic land cards, reveal those cards, put one onto the battlefield tapped and the other into your hand, then shuffle.

Draconic Lore

This spell costs {2} less to cast if you control a Dragon.
Draw three cards.

Wayfarer's Bauble

{2}, {T}, Sacrifice this artifact: Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Counterspell

Dragonmaster Outcast

At the beginning of your upkeep, if you control six or more lands, create a 5/5 red Dragon creature token with flying.

Shamanic Revelation

Draw a card for each creature you control.
Ferocious — You gain 4 life for each creature you control with power 4 or greater.

Swiftfoot Boots

Equipped creature has hexproof and haste. (It can't be the target of spells or abilities your opponents control. It can attack and {T} no matter when it came under your control.)
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Island

Reckless Barbarian

Atarka, World Render

Flying, trample
Whenever a Dragon you control attacks, it gains double strike until end of turn.

Tyrant of Kher Ridges

Flying
When this creature enters, it deals 4 damage to any target.
{R}: This creature gets +1/+0 until end of turn.

Sakura-Tribe Elder

Sacrifice this creature: Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Return of the Wildspeaker

Choose one —
• Draw cards equal to the greatest power among non-Human creatures you control.
• Non-Human creatures you control get +3/+3 until end of turn.

Thrakkus the Butcher

Trample
Whenever Thrakkus attacks, double the power of each Dragon you control until end of turn.

Patron of the Arts

When this creature enters or dies, create a Treasure token. (It's an artifact with "{T}, Sacrifice this token: Add one mana of any color.")

Dragon's Fire

As an additional cost to cast this spell, you may reveal a Dragon card from your hand or choose a Dragon you control.
Dragon's Fire deals 3 damage to target creature or planeswalker. If you revealed a Dragon card or chose a Dragon as you cast this spell, Dragon's Fire deals damage equal to the power of that card or creature instead.

Garruk's Uprising

When this enchantment enters, if you control a creature with power 4 or greater, draw a card.
Creatures you control have trample. (Each of those creatures can deal excess combat damage to the player or planeswalker it's attacking.)
Whenever a creature you control with power 4 or greater enters, draw a card.

Temur Ascendancy

Creatures you control have haste.
Whenever a creature you control with power 4 or greater enters, you may draw a card.

Warstorm Surge

Whenever a creature you control enters, it deals damage equal to its power to any target.

Dragon's Hoard

Whenever a Dragon you control enters, put a gold counter on this artifact.
{T}, Remove a gold counter from this artifact: Draw a card.
{T}: Add one mana of any color.

Jade Orb of Dragonkind

{T}: Add {G}. When you spend this mana to cast a Dragon creature spell, it enters with an additional +1/+1 counter on it and gains hexproof until your next turn. (It can't be the target of spells or abilities your opponents control.)

Temple of the False God

{T}: Add {C}{C}. Activate only if you control five or more lands.

Miirym, Sentinel Wyrm

Flying, ward {2}
Whenever another nontoken Dragon you control enters, create a token that's a copy of it, except the token isn't legendary.

Kessig Wolf Run

{T}: Add {C}.
{X}{R}{G}, {T}: Target creature gets +X/+0 and gains trample until end of turn.

Exotic Orchard

{T}: Add one mana of any color that a land an opponent controls could produce.

Nimbleclaw Adept

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

Ryusei, the Falling Star

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

Swashbuckler Extraordinaire

When this creature enters, create a Treasure token. (It's an artifact with "{T}, Sacrifice this token: Add one mana of any color.")
Whenever you attack, you may sacrifice one or more Treasures. When you do, up to that many target creatures gain double strike until end of turn.

Scourge of Valkas

Flying
Whenever this creature or another Dragon you control enters, it deals X damage to any target, where X is the number of Dragons you control.
{R}: This creature gets +1/+0 until end of turn.

Forest

Blast-Furnace Hellkite

Artifact offering (You may cast this spell as though it had flash by sacrificing an artifact and paying the difference in mana costs between this and the sacrificed artifact. Mana cost includes color.)
Flying, double strike
Creatures attacking your opponents have double strike.

Gaea's Gift

Put a +1/+1 counter on target creature you control. It gains reach, trample, hexproof, and indestructible until end of turn. (It can't be the target of spells or abilities your opponents control. Damage and effects that say "destroy" don't destroy it.)

Dragonspeaker Shaman

Dragon spells you cast cost {2} less to cast.

Reliquary Tower

You have no maximum hand size.
{T}: Add {C}.

Thunderbreak Regent

Flying
Whenever a Dragon you control becomes the target of a spell or ability an opponent controls, this creature deals 3 damage to that player.

Dragonborn Looter

{1}, {T}: Draw a card, then discard a card.

Earthquake

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

Dissonant Wave

Counter target activated or triggered ability from a noncreature source. (Then exile this card. You may cast the creature later from exile.)

Emerald Dragon

Emerald Dragon // Dissonant Wave

Kiora, Behemoth Beckoner

Whenever a creature you control with power 4 or greater enters, draw a card.
−1: Untap target permanent.

Spit Flame

Spit Flame deals 4 damage to target creature.
Whenever a Dragon you control enters, you may pay {R}. If you do, return this card from your graveyard to your hand.

Chain Reaction

Chain Reaction deals X damage to each creature, where X is the number of creatures on the battlefield.

Scaled Nurturer

{T}: Add {G}. When you spend this mana to cast a Dragon creature spell, you gain 2 life.

Rogue's Passage

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

Lozhan, Dragons' Legacy

Flying
Whenever you cast an Adventure or Dragon spell, Lozhan deals damage equal to that spell's mana value to any target that isn't a commander.

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.

Sol Ring

Minion of the Mighty

Menace
Pack tactics — Whenever this creature attacks, if you attacked with creatures with total power 6 or greater this combat, you may put a Dragon creature card from your hand onto the battlefield tapped and attacking.

Arcane Signet

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

Draconic Muralists

When this creature dies, you may search your library for a Dragon card, reveal it, put it into your hand, then shuffle.

Command Tower

Acolyte of Bahamut

Commander creatures you own have "The first Dragon spell you cast each turn costs {2} less to cast."

Dragon Tempest

Whenever a creature you control with flying enters, it gains haste until end of turn.
Whenever a Dragon you control enters, it deals X damage to any target, where X is the number of Dragons you control.

Keiga, the Tide Star

Flying
When Keiga dies, gain control of target creature.

Savage Ventmaw

Flying
Whenever this creature attacks, add {R}{R}{R}{G}{G}{G}. Until end of turn, you don't lose this mana as steps and phases end.

Explore

You may play an additional land this turn.
Draw a card.

Earthquake Dragon

This spell costs {X} less to cast, where X is the total mana value of Dragons you control.
Flying, trample
{2}{G}, Sacrifice a land: Return this card from your graveyard to your hand.

Negate

Return to Nature

Choose one —
• Destroy target artifact.
• Destroy target enchantment.
• Exile target card from a graveyard.

Iymrith, Desert Doom

Flying
Iymrith has ward {4} as long as it's untapped.
Whenever Iymrith deals combat damage to a player, draw a card. Then if you have fewer than three cards in hand, draw cards equal to the difference.

Breath Weapon

Breath Weapon deals 2 damage to each non-Dragon creature.

Ganax, Astral Hunter

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

Korlessa, Scale Singer

You may look at the top card of your library any time.
You may cast Dragon spells from the top of your library.

Psionic Pulse

Counter target noncreature spell. (Then exile this card. You may cast the creature later from exile.)

Sapphire Dragon

Flying
Whenever this creature attacks or blocks, scry 2.

Sapphire Dragon // Psionic Pulse

Crucible of Fire

Lapis Orb of Dragonkind

{T}: Add {U}. When you spend this mana to cast a Dragon creature spell, scry 2. (Look at the top two cards of your library, then put any number of them on the bottom and the rest on top in any order.)

Carnelian Orb of Dragonkind

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

Stirring Bard

Defender
When this creature enters, you take the initiative.
Mantle of Inspiration — {T}: Target creature gains menace and haste until end of turn.

Blur

Exile target creature you control, then return that card to the battlefield under its owner's control.
Draw a card.

Mosswort Bridge

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 {G}.
{G}, {T}: You may play the exiled card without paying its mana cost if creatures you control have total power 10 or greater.