Klimdrag, the Confusing

Morph {t}{w}{b/g}{u/r}, ({5}, cast unside down as a 5/5
with ward 3 and reach.
Flying, ward 3
Legendary creatures you control get +X/+X,
where X is the number of legendary creatures you control.
Whenever you cast a legendary card, mill until you reach another legendary creature card, put it onto
the battlefield.
Sacrifice , Klimdrag, shuffle your graveyard into
your library.