Ali-A Was Here is an Icon Series Fortnite Spray. Ali-A Was Here was first added to the game in Fortnite Chapter 3 Season 2.
The Ali-A Army emote can be unlocked by completing the following quest by May 29, 2022:
Eliminate Opponents at the Ali-A Experience in Epic's Picks. 
This can be done on Fortnite Creative Island: 5135-8778-2901