You control at least seven untapped creatures, two or which are green.
Steps
Cast Ancient Imperiosaur by tapping seven untapped creatures you control, two of which must be green.
Ancient Imperiosaur enters the battlefield with fourteen +1/+1 counters on it.
At the beginning of your next upkeep, Mayael's Aria triggers, causing you to put a +1/+1 counter on each creature you control, gain ten life, and win the game.
Results
Win the game at the beginning of your next upkeep.