Chameleos, Mist Dragon

Changeling (This card is every creature type.)
As Chameleos, Mist Dragon enters the battlefield, choose a creature type.
Spells you cast of the chosen type cost {w}{u}{b}{r}{g} less to cast. This effect reduces only the amount of colored mana you play.
Other creatures you control of the chosen type get +1/+1.
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Precious few sightings of this elder dragon have been recorded, leading to claims it can vanish into its environment like a chameleon.