Tree of the Prism-Leaves

Tree of the Prism-Leaves enters the battlefield
tapped. Sacrifice it unless you control a Forest
and a Plains.
{t}: Add {w} or {g}.
{1}{t}: Convert any number of {w} in your mana
pool to {g} or vice-versa. Gain 1 life.
{2}{w}{g}{t}, Sacrifice Tree of the Prism-Leaves:
Gain 1 life for each Plains and Forest you
control.