Dryad of Endless Bounty

Dryad of Endless Bounty is a forest in
addition to it's other colors and types.
Choose a non-land permanent in your
graveyard, sacrifice X lands, where X is it's
converted mana cost: Return that permanent
to the battlefield under your control. It becomes
a forest in addition to it's other colors and types.
Creatures must help sustain the forest, but
the forest can also help sustain the creatures.