Elesh Norn, Ascendant

0: Put a +1/+1 or -1/-1 counter on up to one target creature, then proliferate.
-3: Each player sacrifices a creature. Put a token copy of one of those creatures onto the battlefield under your control.
-6: Exile all graveyards. You may put any number of creature cards exiled this way with mana value 3 or less onto the battlefield under your control.