Sword of the Paruns attached to Auriok Bladewarden.
({12} magic symbol) (at most) available.
Steps
At the beginning of your upkeep, Mayael's Aria triggers.
Holding priority, activate Auriok Bladewarden by tapping it, giving itself +X/+X until end of turn, where X is its power, which is increased by 2 due to Sword of the Paruns.
Activate Sword of the Paruns by paying ({3} magic symbol) , untapping Auriok Bladewarden.
Repeat from step 2 until Auriok Bladewarden has power nineteen or greater, omitting step 3 on the final iteration.
Resolve the Mayael's Aria trigger from step 1, causing you to put a +1/+1 counter on each creature you control, gain 10 life and win the game.