World Creating Regigigas

{g}: Target Forest becomes a 4/4 elemental with Trample.
{r}: Target Mountain becomes a 4/4 elemental with Haste and Firststrike.
{b}: Target Swamp becomes a 4/4 elemental with deathtouch.
{u} Target Island becomes a 4/4 elemental with Flying.
{w}: Target Plains becomes a 4/4 elemental with Vigilance.
{c}: Target Wastes becomes a 4/4 elemental with {t}: Add {c} to your Mana Pool.