Sparktongue Dragon

Flying
When Sparktongue Dragon enters, you may pay {2}{R}. When you do, it deals 3 damage to any target.

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.

Knollspine Dragon

Flying
When Knollspine Dragon enters, you may discard your hand and draw cards equal to the damage dealt to target opponent this turn.

Tyrant's Familiar

Flying, haste
Lieutenant — As long as you control your commander, Tyrant's Familiar gets +2/+2 and has "Whenever Tyrant's Familiar attacks, it deals 7 damage to target creature defending player controls."

Fellwar Stone

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

Utvara Hellkite

Flying
Whenever a Dragon you control attacks, create a 6/6 red Dragon creature token with flying.

Sol Ring

Bogardan Hellkite

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

Dragon Mage

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

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.

Flameblast Dragon

Flying
Whenever Flameblast Dragon attacks, you may pay {X}{R}. If you do, Flameblast Dragon deals X damage to any target.

Spawn of Thraxes

Flying
When Spawn of Thraxes enters, it deals damage to any target equal to the number of Mountains you control.

Tel-Jilad Stylus

{T}: Put target permanent you own on the bottom of your library.

Siege Dragon

Flying
When Siege Dragon enters, 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.

Hellkite Charger

Flying, haste
Whenever Hellkite Charger attacks, you may pay {5}{R}{R}. If you do, untap all attacking creatures and after this phase, there is an additional combat phase.

Zirilan of the Claw

{1}{R}{R}, {T}: Search your library for a Dragon permanent card, put that card onto the battlefield, then shuffle. That Dragon gains haste until end of turn. Exile it at the beginning of the next end step.

Steel Hellkite

Flying
{2}: Steel Hellkite gets +1/+0 until end of turn.
{X}: Destroy each nonland permanent with mana value X whose controller was dealt combat damage by Steel Hellkite this turn. Activate only once each turn.