Iwa-Ryu, the Earth Dragon

Flying, Trample
Iwa-Ryu's toughness is equal to the number of
lands you control.
Tap all other creatures you control: Swap
Iwa-Ryu's power and toughness until end of
turn.
If Iwa-Ryu would be put into your graveyard
from the battlefield, put her into your library,
second from the top.