Ada, God of the Grave-Mist

Indestructible
As long as your devotion to black, green and blue
is less than ten, Ada isn't a creature.
At the beginning of each player's upkeep,
that player puts the top three cards of their
library into their graveyard.
Whenever a creature is put into a graveyard from
a library, create a 1/1 black and blue Spirit Bird creature token with flying