Dragonspeaker Shaman

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

Arcane Signet

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

Sol Ring

Dragonlord's Servant

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

Territorial Hellkite

Flying, haste
At the beginning of combat on your turn, choose an opponent at random that Territorial Hellkite didn't attack during your last combat. Territorial Hellkite attacks that player this combat if able. If you can't choose an opponent this way, tap Territorial Hellkite.

Talisman of Creativity

{T}: Add {C}.
{T}: Add {U} or {R}. Talisman of Creativity deals 1 damage to you.

Firkraag, Cunning Instigator

Flying, haste
Whenever one or more Dragons you control attack an opponent, goad target creature that player controls.
Whenever a creature deals combat damage to one of your opponents, if that creature had to attack this combat, you put a +1/+1 counter on Firkraag, Cunning Instigator and you draw a card.

Hypersonic Dragon

Flying, haste
You may cast sorcery spells as though they had flash. (You may cast them any time you could cast an instant.)

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.

Izzet Signet

Shimmer Dragon

Flying
As long as you control four or more artifacts, Shimmer Dragon has hexproof.
Tap two untapped artifacts you control: Draw a card.

Warmonger Hellkite

Flying
All creatures attack each combat if able.
{1}{R}: Attacking creatures get +1/+0 until end of turn.