Morophon, the Boundless

Changeling (This card is every creature type.)
As Morophon, the Boundless enters the
battlefield, choose a creature type.
Spells of the chosen type you cast cost{w}{u}{b}{r}{g}less to cast.
This effect reduces
only the amount of colored mana you pay. Other creatures you control of the chosen type
get +1/+1.