Azula, Ruthless Firebender (Extended Art) (184) - Avatar: The Last Airbender: Eternal-Legal

Firebending 1

Whenever Azula attacks, you may discard a card. Then you get an experience counter for each player who discarded a card this turn.

2B: Until end of turn, Azula gets +1/+1 for each experience counter you have and gains menace.