Fortnite Alien Devices - where to collect them and activate the Countermeasure Device

Fortnite Alien Devices and Countermeasure Device locations — (Image credit: Epic Games)

Fortnite Alien Devices are needed to strike back at the extraterrestrial invaders, by using them to activate the Countermeasure Device underneath Corny Complex. It's not yet clear exactly what this machinery hidden in a subterranean base actually does, but it's undoubtedly an important step towards reclaiming control of the Fortnite island as we draw nearer to the endgame for the current season. We don't often see quests with several steps to complete in one go, so make sure you're prepared with our guide to all of the Fortnite Alien Devices locations and how to activate the Countermeasure Device underneath Corny Complex once you have them.

Fortnite Alien Devices locations

To get started on this quest you need to collect three Fortnite Alien Devices, which look like floating purple balls and can be tricky to spot as they blend into their surroundings. Handily they're all located around the outskirts of Corny Complex, as that's your ultimate destination once you've found them, and these are the specific places where you can collect the Fortnite Alien Devices:

At the bottom of the purple clearing northwest of Corny Complex
Near a bush in the purple clearing southwest of Corny Complex
Under a tree in the purple clearing south of Corny Complex

How to activate the Countermeasure Device in Fortnite

Once you've collected the three Fortnite Alien Devices, you then need to activate the Countermeasure Device underneath Corny Complex. This is below the big red barn in the middle of the farm and there are several ways to get into it, though for the purposes of this quest the easiest entry method is to use the electronic door cut into the rock face on the east side of the barn.

Go left from that entrance, then take the corridor on the left to reach the southwest room containing the Countermeasure Device, which you can interact with to complete this quest. Be wary that this underground base is guarded by Fortnite IO Guards and Doctor Slone herself, so try to dash through the area and activate the Countermeasure Device while avoiding a protracted firefight.