When you make an attack roll or ability check, you can take a Bonus Action to gain Advantage on the roll. Alternatively, you can impose Disadvantage on a saving throw a creature makes against a Warmage cantrip you cast before the end of your turn.
You can use this feature a number of times equal to your Intelligence modifier (minimum of once). You regain one of its expended uses when you finish a Short Rest, and you regain all expended uses when you finish a Long Rest.