Klauth, Unrivaled Ancient

Flying, haste
Whenever Klauth, Unrivaled Ancient attacks, add X mana in any combination of colors, where X is the total power of attacking creatures. Spend this mana only to cast spells. Until end of turn, you don't lose this mana as steps and phases end.

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.

Monastery Siege

As Monastery Siege enters the battlefield, choose Khans or Dragons.
• Khans — At the beginning of your draw step, draw an additional card, then discard a card.
• Dragons — Spells your opponents cast that target you or a permanent you control cost {2} more to cast.

Island

Rishkar's Expertise

Draw cards equal to the greatest power among creatures you control.
You may cast a spell with mana value 5 or less from your hand without paying its mana cost.

Niv-Mizzet, the Firemind

Flying
Whenever you draw a card, Niv-Mizzet, the Firemind deals 1 damage to any target.
{T}: Draw a card.

Cultivate

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.

Arcane Denial

Counter target spell. Its controller may draw up to two cards at the beginning of the next turn's upkeep.
You draw a card at the beginning of the next turn's upkeep.

Dragon Broodmother

Flying
At the beginning of each upkeep, create a 1/1 red and green Dragon creature token with flying and devour 2. (As the token enters the battlefield, you may sacrifice any number of creatures. It enters the battlefield with twice that many +1/+1 counters on it.)

Lozhan, Dragons' Legacy

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

Return to Nature

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

Opportunistic Dragon

Flying
When Opportunistic Dragon enters the battlefield, choose target Human or artifact an opponent controls. For as long as Opportunistic Dragon remains on the battlefield, gain control of that permanent, it loses all abilities, and it can't attack or block.

Ferrous Lake

Rimewood Falls

({T}: Add {G} or {U}.)
Rimewood Falls enters the battlefield tapped.

Terror of Mount Velus

Flying, double strike
When Terror of Mount Velus enters the battlefield, creatures you control gain double strike until end of turn.

Robe of Mirrors

Enchant creature (Target a creature as you cast this. This card enters the battlefield attached to that creature.)
Enchanted creature has shroud. (It can't be the target of spells or abilities.)

Counterspell

Mossfire Valley

Concentrate

Command Tower

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

Izzet Boilerworks

Izzet Boilerworks enters the battlefield tapped.
When Izzet Boilerworks enters the battlefield, return a land you control to its owner's hand.
{T}: Add {U}{R}.

Llanowar Elves

Farseek

Search your library for a Plains, Island, Swamp, or Mountain card, put it onto the battlefield tapped, then shuffle.

Wild Growth

Enchant land
Whenever enchanted land is tapped for mana, its controller adds an additional {G}.

Displace

Exile up to two target creatures you control, then return those cards to the battlefield under their owner's control.

An Offer You Can't Refuse

Counter target noncreature spell. Its controller creates two Treasure tokens. (They're artifacts with "{T}, Sacrifice this artifact: Add one mana of any color.")

Chain Reaction

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

Thunderbreak Regent

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

Naturalize

Frontier Bivouac

Frontier Bivouac enters the battlefield tapped.
{T}: Add {G}, {U}, or {R}.

Kindred Discovery

As Kindred Discovery enters the battlefield, choose a creature type.
Whenever a creature you control of the chosen type enters the battlefield or attacks, draw a card.

Lightning Greaves

Equipped creature has haste and shroud. (It can't be the target of spells or abilities.)
Equip {0}

Shivan Dragon

Flying (This creature can't be blocked except by creatures with flying or reach.)
{R}: Shivan Dragon gets +1/+0 until end of turn.

Dragonspeaker Shaman

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

Shivan Hellkite

Flying (This creature can't be blocked except by creatures with flying or reach.)
{1}{R}: Shivan Hellkite deals 1 damage to any target.

Anger

Haste
As long as Anger is in your graveyard and you control a Mountain, creatures you control have haste.

Sight of the Scalelords

At the beginning of combat on your turn, creatures you control with toughness 4 or greater get +2/+2 and gain vigilance until end of turn.

Utopia Sprawl

Enchant Forest
As Utopia Sprawl enters the battlefield, choose a color.
Whenever enchanted Forest is tapped for mana, its controller adds an additional one mana of the chosen color.

Terramorphic Expanse

{T}, Sacrifice Terramorphic Expanse: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

Dragon Roost

{5}{R}{R}: Create a 5/5 red Dragon creature token with flying. (It can't be blocked except by creatures with flying or reach.)

Lathliss, Dragon Queen

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

Sarkhan, Soul Aflame

Dragon spells you cast cost {1} less to cast.
Whenever a Dragon enters the battlefield under your control, you may have Sarkhan, Soul Aflame become a copy of it until end of turn, except its name is Sarkhan, Soul Aflame and it's legendary in addition to its other types.

Vineglimmer Snarl

As Vineglimmer Snarl enters the battlefield, you may reveal a Forest or Island card from your hand. If you don't, Vineglimmer Snarl enters the battlefield tapped.
{T}: Add {G} or {U}.

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.

Worn Powerstone

Worn Powerstone enters the battlefield tapped.
{T}: Add {C}{C}.

Highland Forest

({T}: Add {R} or {G}.)
Highland Forest enters the battlefield tapped.

Chaos Dragon

Flying, haste
Chaos Dragon attacks each combat if able.
At the beginning of combat on your turn, each player rolls a d20. If one or more opponents had the highest result, Chaos Dragon can't attack those players or planeswalkers they control this combat.

Sol Ring

Mountain

Goblin Anarchomancer

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

Curse of Clinging Webs

Enchant player
Whenever a nontoken creature enchanted player controls dies, exile it and you create a 1/2 green Spider creature token with reach.

Swiftfoot Boots

Equipped creature has hexproof and haste. (It can't be the target of spells or abilities your opponents control.)
Equip {1}

Overflowing Basin

Arcane Signet

Aether Flash

Whenever a creature enters the battlefield, Aether Flash deals 2 damage to it.

Leyline of Anticipation

If Leyline of Anticipation is in your opening hand, you may begin the game with it on the battlefield.
You may cast spells as though they had flash.

Garruk's Uprising

When Garruk's Uprising enters the battlefield, if you control a creature with power 4 or greater, draw a card.
Creatures you control have trample. (They can deal excess combat damage to the player or planeswalker they're attacking.)
Whenever a creature with power 4 or greater enters the battlefield under your control, draw a card.

Alpha Authority

Enchant creature
Enchanted creature has hexproof and can't be blocked by more than one creature.

Rampant Growth

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

Ryusei, the Falling Star

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

Myriad Landscape

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

Oversimplify

Exile all creatures. Each player creates a 0/0 green and blue Fractal creature token and puts a number of +1/+1 counters on it equal to the total power of creatures they controlled that were exiled this way.

Skyship Stalker

Flying
{R}: Skyship Stalker gets +1/+0 until end of turn.
{R}: Skyship Stalker gains first strike until end of turn.
{R}: Skyship Stalker gains haste until end of turn.

Elvish Mystic

Thrakkus the Butcher

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

Miirym, Sentinel Wyrm

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

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

Beast Within

Destroy target permanent. Its controller creates a 3/3 green Beast creature token.

Path of Ancestry

Path of Ancestry enters the battlefield tapped.
{T}: Add one mana of any color in your commander's color identity. When that mana is spent to cast a creature spell that shares a creature type with your commander, scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Skyline Despot

Flying
When Skyline Despot enters the battlefield, 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.

Akoum Hellkite

Flying
Landfall — Whenever a land enters the battlefield under your control, Akoum Hellkite deals 1 damage to any target. If that land is a Mountain, Akoum Hellkite deals 2 damage instead.

Whispersilk Cloak

Equipped creature can't be blocked and has shroud. (It can't be the target of spells or abilities.)
Equip {2}

Swerve

Change the target of target spell with a single target.

Exotic Orchard

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

Wilt

Destroy target artifact or enchantment.
Cycling {2} ({2}, Discard this card: Draw a card.)

Fyndhorn Elves

Iymrith, Desert Doom

Flying
Iymrith, Desert Doom 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.

Forest

Colossal Majesty

At the beginning of your upkeep, if you control a creature with power 4 or greater, draw a card.

Nephalia Smuggler

{3}{U}, {T}: Exile another target creature you control, then return that card to the battlefield under your control.

Temur Ascendancy

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

Frostboil Snarl

As Frostboil Snarl enters the battlefield, you may reveal an Island or Mountain card from your hand. If you don't, Frostboil Snarl enters the battlefield tapped.
{T}: Add {U} or {R}.

Coastal Piracy

Whenever a creature you control deals combat damage to an opponent, you may draw a card.

Bala Ged Sanctuary

Bala Ged Sanctuary enters the battlefield tapped.
{T}: Add {G}.

Bala Ged Recovery

Return target card from your graveyard to your hand.

Bala Ged Recovery // Bala Ged Sanctuary

Dragonlord's Servant

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

Scourge of the Throne

Flying
Dethrone (Whenever this creature attacks the player with the most life or tied for most life, put a +1/+1 counter on it.)
Whenever Scourge of the Throne attacks for the first time each turn, if it's attacking the player with the most life or tied for most life, untap all attacking creatures. After this phase, there is an additional combat phase.

Ghostly Flicker

Exile two target artifacts, creatures, and/or lands you control, then return those cards to the battlefield under your control.

Atarka, World Render

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

Ganax, Astral Hunter

Flying
Whenever Ganax, Astral Hunter or another Dragon enters the battlefield under your control, 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.)

Adrix and Nev, Twincasters

Ward {2} (Whenever this creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays {2}.)
If one or more tokens would be created under your control, twice that many of those tokens are created instead.

Loch Dragon

Flying
Whenever Loch Dragon enters the battlefield or attacks, you may discard a card. If you do, draw a card.

Bolt Bend

This spell costs {3} less to cast if you control a creature with power 4 or greater.
Change the target of target spell or ability with a single target.

Obsidian Charmaw

This spell costs {1} less to cast for each land your opponents control that could produce {C}.
Flying
When Obsidian Charmaw enters the battlefield, destroy target nonbasic land an opponent controls.

Ram Through

Target creature you control deals damage equal to its power to target creature you don't control. If the creature you control has trample, excess damage is dealt to that creature's controller instead.

Siege Dragon

Flying
When Siege Dragon enters the battlefield, destroy all Walls your opponents control.
Whenever Siege Dragon attacks, if defending player controls no Walls, it deals 2 damage to each creature without flying that player controls.

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.

Dragon Mage

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

Kindred Summons

Choose a creature type. Reveal cards from the top of your library until you reveal X creature cards of the chosen type, where X is the number of creatures you control of that type. Put those cards onto the battlefield, then shuffle the rest of the revealed cards into your library.

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.

Krosan Grip

Split second (As long as this spell is on the stack, players can't cast spells or activate abilities that aren't mana abilities.)
Destroy target artifact or enchantment.

Windfall

Each player discards their hand, then draws cards equal to the greatest number of cards a player discarded this way.

Savage Ventmaw

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

Thunder Dragon

Flying
When Thunder Dragon enters the battlefield, it deals 3 damage to each creature without flying.

Bogardan Hellkite

Flash
Flying
When Bogardan Hellkite enters the battlefield, it deals 5 damage divided as you choose among any number of targets.

Nature's Lore

Search your library for a Forest card, put that card onto the battlefield, then shuffle.