Azorius Ascendancy

{2}{w}{u}: The next instant spell you cast this turn
gains Addendum —Draw a card.
Whenever you cast an instant spell during your mainphase, put an authority counter on Azorius Ascendancy.
At the beginning of your upkeep, if Azorius Ascendancy has 15 or more authority counters
on it, you win the game.