Complete the second tier of the challenge “Heroic Banter"
The second tier of Heroic Banter requires you to taunt 25 times.
Taunts aren’t really used for anything other than, uhh, taunting your opponent. You’ll be vulnerable when doing it, but try to sneak a few in during matches while you play through arcade mode. You can also just stand and taunt over and over in a local match with a second controller. Taunts are performed differently in each game.