Aerona, Vitality's Herald

+1: Put a +1/+1 counter on up to one target creature you control. It gains flying until end of turn.
-3: Until end of turn, whenever a creature deals combat damage to a player, you may draw a card. If you do, create a 1/1 green Elf creature token
-7: Populate X times, where X is the number of creatures you control with +1/+1 counters on them.