Personify

Exile target creature you control, then return that card to the battlefield under its owner's control. Create a 1/1 colorless Shapeshifter creature token with changeling. (It's every creature type.)

Three Tree Mascot

Changeling (This card is every creature type.)
{1}: Add one mana of any color. Activate only once each turn.

Dragonlord's Servant

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

Caustic Exhale

As an additional cost to cast this spell, behold a Dragon or pay {1}. (To behold a Dragon, choose a Dragon you control or reveal a Dragon card from your hand.)
Target creature gets -3/-3 until end of turn.

Mox Jasper

{T}: Add one mana of any color. Activate only if you control a Dragon.

Sarkhan, Dragon Ascendant

When Sarkhan enters, you may behold a Dragon. If you do, create a Treasure token. (To behold a Dragon, choose a Dragon you control or reveal a Dragon card from your hand.)
Whenever a Dragon you control enters, put a +1/+1 counter on Sarkhan. Until end of turn, Sarkhan becomes a Dragon in addition to its other types and gains flying.