Counterspell

Mirror Image

You may have Mirror Image enter as a copy of a creature you control.

Temur Ascendancy

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

Somberwald Sage

{T}: Add three mana of any one color. Spend this mana only to cast creature spells.

Karplusan Forest

{T}: Add {C}.
{T}: Add {R} or {G}. Karplusan Forest deals 1 damage to you.

Frontier Siege

As Frontier Siege enters, choose Khans or Dragons.
• Khans — At the beginning of each of your main phases, add {G}{G}.
• Dragons — Whenever a creature with flying enters under your control, you may have it fight target creature you don't control.

Rhythm of the Wild

Creature spells you control can't be countered.
Nontoken creatures you control have riot. (They enter with your choice of a +1/+1 counter or haste.)

Rapacious Dragon

Flying
When this creature enters, create two Treasure tokens. (They're artifacts with "{T}, Sacrifice this token: Add one mana of any color.")

Shivan Reef

{T}: Add {C}.
{T}: Add {U} or {R}. Shivan Reef deals 1 damage to you.

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.

Hinterland Harbor

Hinterland Harbor enters tapped unless you control a Forest or an Island.
{T}: Add {G} or {U}.

Rattleclaw Mystic

{T}: Add {G}, {U}, or {R}.
Morph {2} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)
When Rattleclaw Mystic is turned face up, add {G}{U}{R}.

Dreamroot Cascade

Dreamroot Cascade enters tapped unless you control two or more other lands.
{T}: Add {G} or {U}.

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.

Sakura-Tribe Elder

Sacrifice Sakura-Tribe Elder: Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Yavimaya Coast

{T}: Add {C}.
{T}: Add {G} or {U}. Yavimaya Coast deals 1 damage to you.

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 Haven of the Spirit Dragon: Return target Dragon creature card or Ugin planeswalker card from your graveyard to your hand.

Scourge of Valkas

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

Carnelian Orb of Dragonkind

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

Nature's Lore

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

Displace

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

Dragonborn Champion

Trample
Whenever a source you control deals 5 or more damage to a player, draw a card.

Arcane Signet

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

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.

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.

Waterlogged Grove

{T}, Pay 1 life: Add {G} or {U}.
{1}, {T}, Sacrifice Waterlogged Grove: Draw a card.

Cursed Mirror

{T}: Add {R}.
As Cursed Mirror enters, you may have it become a copy of any creature on the battlefield until end of turn, except it has haste.

Rising of the Day

Creatures you control have haste.
Legendary creatures you control get +1/+0.

Patron of the Arts

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

Cascade Bluffs

{T}: Add {C}.
{U/R}, {T}: Add {U}{U}, {U}{R}, or {R}{R}.

Exotic Orchard

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

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.

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.)

Thunder Dragon

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

Dragonspeaker Shaman

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

Negate

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.)

Niv-Mizzet, Dracogenius

Flying
Whenever Niv-Mizzet, Dracogenius deals damage to a player, you may draw a card.
{U}{R}: Niv-Mizzet, Dracogenius deals 1 damage to any target.

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.

Sol Ring

Hull Breach

Choose one —
• Destroy target artifact.
• Destroy target enchantment.
• Destroy target artifact and target enchantment.

Bountiful Landscape

{T}: Add {C}.
{T}, Sacrifice Bountiful Landscape: Search your library for a basic Forest, Island, or Mountain card, put it onto the battlefield tapped, then shuffle.
Cycling {G}{U}{R} ({G}{U}{R}, Discard this card: Draw a card.)

Bower Passage

Creatures with flying can't block creatures you control.

Unclaimed Territory

As Unclaimed Territory enters, choose a creature type.
{T}: Add {C}.
{T}: Add one mana of any color. Spend this mana only to cast a creature spell of the chosen type.

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.

Crucible of Fire

Goblin Anarchomancer

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

Nature's Claim

Destroy target artifact or enchantment. Its controller gains 4 life.

Stubborn Denial

Counter target noncreature spell unless its controller pays {1}.
Ferocious — If you control a creature with power 4 or greater, counter that spell instead.

Reflections of Littjara

As Reflections of Littjara enters, choose a creature type.
Whenever you cast a spell of the chosen type, copy that spell. (A copy of a permanent spell becomes a token.)

Rockfall Vale

Rockfall Vale enters tapped unless you control two or more other lands.
{T}: Add {R} or {G}.

Sulfur Falls

Sulfur Falls enters tapped unless you control an Island or a Mountain.
{T}: Add {U} or {R}.

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.)

Flooded Grove

{T}: Add {C}.
{G/U}, {T}: Add {G}{G}, {G}{U}, or {U}{U}.

Distant Melody

Choose a creature type. Draw a card for each permanent you control of that type.

Forest

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.

Farseek

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

Stormcarved Coast

Stormcarved Coast enters tapped unless you control two or more other lands.
{T}: Add {U} or {R}.

Minion of the Mighty

Menace
Pack tactics — Whenever Minion of the Mighty 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.

Rampant Growth

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

Mountain

Cinder Glade

({T}: Add {R} or {G}.)
Cinder Glade enters tapped unless you control two or more basic lands.

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 you control enters, create a token that's a copy of it, except the token isn't legendary.

Frontier Bivouac

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

Ghostly Flicker

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

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.

Ferrous Lake

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.

Dragon's Hoard

Whenever a Dragon you control enters, put a gold counter on Dragon's Hoard.
{T}, Remove a gold counter from Dragon's Hoard: Draw a card.
{T}: Add one mana of any color.

Mossfire Valley

Wild Growth

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

Monstrous Vortex

Whenever you cast a creature spell with power 5 or greater, discover X, where X is that spell's mana value. (Exile cards from the top of your library until you exile a nonland card with that mana value or less. Cast it without paying its mana cost or put it into your hand. Put the rest on the bottom in a random order.)

Secluded Courtyard

As this land enters, choose a creature type.
{T}: Add {C}.
{T}: Add one mana of any color. Spend this mana only to cast a creature spell of the chosen type or activate an ability of a creature source of the chosen type.

Skyshroud Claim

Search your library for up to two Forest cards, put them onto the battlefield, then shuffle.

Orb of Dragonkind

{1}, {T}: Add two mana in any combination of colors. Spend this mana only to cast Dragon spells or activate abilities of Dragons.
{R}, {T}, Sacrifice Orb of Dragonkind: Look at the top seven cards of your library. You may reveal a Dragon card from among them and put it into your hand. Put the rest on the bottom of your library in a random order.

Dragonlord's Servant

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

Path of Ancestry

Path of Ancestry enters 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.)

Ryusei, the Falling Star

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

Atarka, World Render

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

Scaled Nurturer

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

Command Tower

Wrap in Vigor

Destiny Spinner

Creature and enchantment spells you control can't be countered.
{3}{G}: Target land you control becomes an X/X Elemental creature with trample and haste until end of turn, where X is the number of enchantments you control. It's still a land.

Rootbound Crag

Rootbound Crag enters tapped unless you control a Mountain or a Forest.
{T}: Add {R} or {G}.

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 Earthquake Dragon from your graveyard to your hand.

Island

Overflowing Basin

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.