Entmoot

All Treefolk have Defender.
At the end of your turn, you may sacrifice a
Forest to create a green Treefolk creature token
with "This creature's power and toughness are
equal to the number of Treefolk in play."
Sacrifice Entmoot: Search your library for X
basic Forest cards, where X is equal to the
number of Treefolk you control, put them on
the battlefield tapped, and shuffle your library.