This challenge is part of Fortnite Season 4 Week 5 Challenges and you'll have to make a Stark Robot dance. It's possible since Season 4 to command these armed humanoids. They can be found in two kinds of places: Stark Industries and Quinjet Patrol landing sites.
We highly recommend the Quinjet landing sites, which are much less contested than the Iron Man location.
It's possible to find out where Quinjet land while you're still in the battle bus. All you have to do is spot the blue smoke trails on the ground while you're in-game, or check your mini map when the battle bus is halfway there. Markers will be displayed to show you Quinjet Patrol landing sites.
Once you have a site in your sights, the most efficient way to do it is to land not far from it — where you can find one or two weapons. Storm the ship on the ground, and shoot down the Stark robots guarding the place (without finishing them off on the ground).
Then approach one of the knocked-out robots, hack it, and perform any dance emote. It will start its own dance, and the challenge will be completed.
Original content by Romain "Zorg" Becquelin.