Unifier of Dragons

Dragons may be affected as if they are
all colors of mana.
Dragons are required to be cast with a singular
mana of each type, replacing a singular generic.
If there is not enough generic mana required to
cast it with each mana type, cast it with your choice
of mana being used.
"The Unifer is the one who has brought order to the Dragons, an order that even Tiamat respects."