Nana, Tutor of All Might

Trample. This creature enters the battlefield with
+1,+1 counters on it equal to the number of creatures on the battlefield when you would be
dealt 10 or more damage in one turn you may
remove a counter from this creature if you do
prevent 10 of the damage that would be dealt
to you this way (This ability can only be activated
once per turn)
This creature cant attack as long as it has power
10 or greater