Old Growth

Search your library for a Forest card and put it
onto the battlefield tapped, then shuffle your
library.
If you control five or more Forests, destroy up to
one target artifact or enchantment. If you control
seven or more Forests, return up to one target
card from your graveyard to your hand. If you
control nine or more Forests, create Skog, a
legendary 8/8 green Elder Troll creature token
with hexproof and trample.