Dispelling Exhale

As an additional cost to cast this spell, you may behold a Dragon. (You may choose a Dragon you control or reveal a Dragon card from your hand.)
Counter target spell unless its controller pays {2}. If a Dragon was beheld, counter that spell unless its controller pays {4} instead.

Inundated Archive

This land enters tapped.
{T}: Add {U} or {B}.

Waterlogged Teachings

Search your library for an instant card or a card with flash, reveal it, put it into your hand, then shuffle.

Waterlogged Teachings // Inundated Archive

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.)

Entropic Cloud

Creatures you control gain deathtouch until end of turn. (Then exile this card. You may cast the creature later from exile.)

Topaz Dragon

Topaz Dragon // Entropic Cloud

Ice Tunnel

({T}: Add {U} or {B}.)
This land enters tapped.

Dragonstorm Globe

Each Dragon you control enters with an additional +1/+1 counter on it.
{T}: Add one mana of any color.

Dragonborn Looter

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

Roiling Dragonstorm

When this enchantment enters, draw two cards, then discard a card.
When a Dragon you control enters, return this enchantment to its owner's hand.

Juvenile Mist Dragon

Flying
Confounding Clouds — When this creature 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.

Sign in Blood

Target player draws two cards and loses 2 life.

Negate

Junji, the Midnight Sky

Flying, menace
When Junji dies, choose one —
• Each opponent discards two cards and loses 2 life.
• Put target non-Dragon creature card from a graveyard onto the battlefield under your control. You lose 2 life.

Overkill

Target creature gets -0/-9999 until end of turn.

Countersquall

Counter target noncreature spell. Its controller loses 2 life.

Keiga, the Tide Star

Flying
When Keiga dies, gain control of target creature.

Temple of the False God

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

Feywild Visitor

Commander creatures you own have "Whenever one or more nontoken creatures you control deal combat damage to a player, you create a 1/1 blue Faerie Dragon creature token with flying."

Aetherize

Return all attacking creatures to their owner's hand.

Counterspell

Bident of Thassa

Whenever a creature you control deals combat damage to a player, you may draw a card.
{1}{U}, {T}: Creatures your opponents control attack this turn if able.

Dimir Signet

Hraesvelgr of the First Brood

Flying, vigilance, ward {2}
Shiva's Aid — When Hraesvelgr enters and whenever you cast a noncreature spell, target creature gets +1/+0 until end of turn and can't be blocked this turn.

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.

Silumgar's Scorn

As an additional cost to cast this spell, you may reveal a Dragon card from your hand.
Counter target spell unless its controller pays {1}. If you revealed a Dragon card or controlled a Dragon as you cast this spell, counter that spell instead.

Yiazmat, Ultimate Mark

{1}{B}, Sacrifice another creature or artifact: Yiazmat gains indestructible until end of turn. Tap it.

Sidequest: Hunt the Mark

When this enchantment enters, destroy up to one target creature.
At the beginning of your end step, if a creature died under an opponent's control this turn, create a Treasure token. Then if you control three or more Treasures, transform this enchantment.

Sidequest: Hunt the Mark // Yiazmat, Ultimate Mark

Arcane Signet

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

Fearsome Awakening

Return target creature card from your graveyard to the battlefield. If it's a Dragon, put two +1/+1 counters on it.

Draconic Lore

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

Coil and Catch

Draw three cards, then discard a card. (Then shuffle this card into its owner's library.)

Marang River Regent

Flying
When this creature enters, return up to two other target nonland permanents to their owners' hands.

Marang River Regent // Coil and Catch

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.

Swamp

Transcendent Dragon

Flash
Flying
When this creature enters, if you cast it, counter target spell. If that spell is countered this way, exile it instead of putting it into its owner's graveyard, then you may cast it without paying its mana cost.

Mind Stone

{T}: Add {C}.
{1}, {T}, Sacrifice this artifact: Draw a card.

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.)

Silumgar's Command

Choose two —
• Counter target noncreature spell.
• Return target permanent to its owner's hand.
• Target creature gets -3/-3 until end of turn.
• Destroy target planeswalker.

Silumgar Monument

{T}: Add {U} or {B}.
{4}{U}{B}: This artifact becomes a 4/4 blue and black Dragon artifact creature with flying until end of turn.

Dragonologist

When this creature enters, look at the top six cards of your library. You may reveal an instant, sorcery, or Dragon card from among them and put it into your hand. Put the rest on the bottom of your library in a random order.
Untapped Dragons you control have hexproof.

Sand Augury

Scry 1, then draw a card. (Then exile this card. You may cast the creature later from exile.)

Young Blue Dragon

Young Blue Dragon // Sand Augury

Icefall Regent

Flying
When this creature enters, tap target creature an opponent controls. That creature doesn't untap during its controller's untap step for as long as you control this creature.
Spells your opponents cast that target this creature cost {2} more to cast.

Command Tower

Haven of the Spirit Dragon

{T}: Add {C}.
{T}: Add one mana of any color. Spend this mana only to cast a Dragon creature spell.
{2}, {T}, Sacrifice this land: Return target Dragon creature card or Ugin planeswalker card from your graveyard to your hand.

Underground River

{T}: Add {C}.
{T}: Add {U} or {B}. This land deals 1 damage to you.

Kefnet's Monument

Blue creature spells you cast cost {1} less to cast.
Whenever you cast a creature spell, target creature an opponent controls doesn't untap during its controller's next untap step.

Darkwater Catacombs

Choked Estuary

As this land enters, you may reveal an Island or Swamp card from your hand. If you don't, this land enters tapped.
{T}: Add {U} or {B}.

Dark Ritual

Dragonlord's Prerogative

As an additional cost to cast this spell, you may reveal a Dragon card from your hand.
If you revealed a Dragon card or controlled a Dragon as you cast this spell, this spell can't be countered.
Draw four cards.

Kairi, the Swirling Sky

Flying, ward {3}
When Kairi dies, choose one —
• Return any number of target nonland permanents with total mana value 6 or less to their owners' hands.
• Mill six cards, then return up to two instant and/or sorcery cards from your graveyard to your hand.

Deceptive Frostkite

Flying
You may have this creature enter as a copy of a creature you control with power 4 or greater, except it's a Dragon in addition to its other types and it has flying.

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.

Dimir Aqueduct

This land enters tapped.
When this land enters, return a land you control to its owner's hand.
{T}: Add {U}{B}.

Winged Words

This spell costs {1} less to cast if you control a creature with flying.
Draw two cards.

Island

Sky Diamond

This artifact enters tapped.
{T}: Add {U}.

Charcoal Diamond

This artifact enters tapped.
{T}: Add {B}.

Drowned Catacomb

This land enters tapped unless you control an Island or a Swamp.
{T}: Add {U} or {B}.

Sol Ring

Frantic Search

Draw two cards, then discard two cards. Untap up to three lands.

Silumgar, the Drifting Death

Flying, hexproof
Whenever a Dragon you control attacks, creatures defending player controls get -1/-1 until end of turn.

Bonders' Enclave

{T}: Add {C}.
{3}, {T}: Draw a card. Activate only if you control a creature with power 4 or greater.

Dusk Sight

Put a +1/+1 counter on up to one target creature. Draw a card. (Then shuffle this card into its owner's library.)

Feral Deathgorger

Flying, deathtouch
When this creature enters, exile up to two target cards from a single graveyard.

Feral Deathgorger // Dusk Sight

Temple of Deceit

This land enters tapped.
When this land enters, scry 1. (Look at the top card of your library. You may put that card on the bottom.)
{T}: Add {U} or {B}.

Night's Whisper

Dragonlord Silumgar

Flying, deathtouch
When Dragonlord Silumgar enters, gain control of target creature or planeswalker for as long as you control Dragonlord Silumgar.

Sudden Spoiling

Split second (As long as this spell is on the stack, players can't cast spells or activate abilities that aren't mana abilities.)
Until end of turn, creatures target player controls lose all abilities and have base power and toughness 0/2.

Flatline

Creatures your opponents control have base power and toughness 0/1 until end of turn.

Talisman of Dominance

{T}: Add {C}.
{T}: Add {U} or {B}. This artifact deals 1 damage to you.

Mass Diminish

Until your next turn, creatures target player controls have base power and toughness 1/1.
Flashback {3}{U} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Bile Blight

Target creature and all other creatures with the same name as that creature get -3/-3 until end of turn.

Eternal Thirst

Enchant creature
Enchanted creature has lifelink and "Whenever a creature an opponent controls dies, put a +1/+1 counter on this creature." (Damage dealt by a creature with lifelink also causes its controller to gain that much life.)

Ravenform

Exile target artifact or creature. Its controller creates a 1/1 blue Bird creature token with flying.
Foretell {U} (During your turn, you may pay {2} and exile this card from your hand face down. Cast it on a later turn for its foretell cost.)

Ebondeath, Dracolich

Flash
Flying
Ebondeath enters tapped.
You may cast this card from your graveyard if a creature not named Ebondeath, Dracolich died this turn.

Sunken Hollow

({T}: Add {U} or {B}.)
This land enters tapped unless you control two or more basic lands.

Ash Barrens

{T}: Add {C}.
Basic landcycling {1} ({1}, Discard this card: Search your library for a basic land card, reveal it, put it into your hand, then shuffle.)

Soul Manipulation

Choose one or both —
• Counter target creature spell.
• Return target creature card from your graveyard to your hand.

Crux of Fate

Choose one —
• Destroy all Dragon creatures.
• Destroy all non-Dragon creatures.

Necromaster Dragon

Flying
Whenever this creature deals combat damage to a player, you may pay {2}. If you do, create a 2/2 black Zombie creature token and each opponent mills two cards.

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

Nimbleclaw Adept

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

Exude Toxin

Each non-Dragon creature gets -X/-X until end of turn. (Then shuffle this card into its owner's library.)

Scavenger Regent

Scavenger Regent // Exude Toxin

Polymorphist's Jest

Until end of turn, each creature target player controls loses all abilities and becomes a blue Frog with base power and toughness 1/1.

Sivitri, Dragon Master

+1: Until your next turn, creatures can't attack you or planeswalkers you control unless their controller pays 2 life for each of those creatures.
−3: Search your library for a Dragon card, reveal it, put it into your hand, then shuffle.
−7: Destroy all non-Dragon creatures.
Sivitri, Dragon Master can be your commander.