Aseria, Caller of Dragons

Double Strike, Vigilance
Aseria can't be countered.
{t}: Add {g}{g} to your manapool.
{2}{g}{g}: Create a 4/4 Dragon creature token with flying and trample.
{4}{g}{g}: Create an 6/6 Grand Dragon creature
token with flying, trample and first strike.
{8}{g}{g}: Create a 10/10 Elder Dragon creature
token with flying, trample, first strike and
indestructible.