Dragonskull Summit

This land enters tapped unless you control a Swamp or a Mountain.
{T}: Add {B} or {R}.

Dismal Backwater

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

Mountain

Lightning Strike

Lightning Strike deals 3 damage to any target.

Niv-Mizzet, Parun

This spell can't be countered.
Flying
Whenever you draw a card, Niv-Mizzet deals 1 damage to any target.
Whenever a player casts an instant or sorcery spell, you draw a card.

Nicol Bolas, the Arisen

+2: Draw two cards.
−3: Nicol Bolas deals 10 damage to target creature or planeswalker.
−4: Put target creature or planeswalker card from a graveyard onto the battlefield under your control.
−12: Exile all but the bottom card of target player's library.

Nicol Bolas, the Ravager

Flying
When Nicol Bolas enters, each opponent discards a card.
{4}{U}{B}{R}: Exile Nicol Bolas, then return him to the battlefield transformed under his owner's control. Activate only as a sorcery.

Nicol Bolas, the Ravager // Nicol Bolas, the Arisen

Verix Bladewing

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

Shock

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

Bloodfell Caves

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

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.

Lathliss, Dragon Queen

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

Skarrgan Hellkite

Riot (This creature enters with your choice of a +1/+1 counter or haste.)
Flying
{3}{R}: This creature deals 2 damage divided as you choose among one or two targets. Activate only if this creature has a +1/+1 counter on it.

Demanding Dragon

Flying
When this creature enters, it deals 5 damage to target opponent unless that player sacrifices a creature of their choice.

Sulfur Falls

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

Sarkhan, Fireblood

+1: You may discard a card. If you do, draw a card.
+1: Add two mana in any combination of colors. Spend this mana only to cast Dragon spells.
−7: Create four 5/5 red Dragon creature tokens with flying.

Maelstrom of the Spirit Dragon

{T}: Add {C}.
{T}: Add one mana of any color. Spend this mana only to cast a Dragon spell or an Omen spell.
{4}, {T}, Sacrifice this land: Search your library for a Dragon card, reveal it, put it into your hand, then shuffle.