Nadia, Keeper of the books.

Indastructable,
Whenever Nadia, Keeper of Books deals combat
damage to a player search your library for a
permanate.
{2}{w/u}{t} Play an Azorius, blue, or white card from
your hand without paying its mana cost.
{3}{w/u}{w/u}: Nadia, Keeper of Books gains
unblockable until end of turn.