Gaea's Liege

As long as Gaea's Liege isn't attacking, its power
and toughness are each equal to the number of
Forests you control. As long as Gaea's Liege is
attacking, its power and toughness are each
equal to the number of Forests defending
player controls.
{t}: Target land becomes a Forest until Gaea's
Liege leaves the battlefield.