The Alien Decryptor is a building in the scenario Hacking Alien Tech. It is unlocked by finishing the Hackers of the Bolt HQ quest, Factory Hack. It requires 1000 
, 900 
, 300 
, and 100 
to build, and 3000 
as research cost.
Building it allows the player to remove the blue aura found on the other islands, allowing the player to build on them.
The scenario Hacking Alien Tech is considered over after building the Alien Decryptor, however the player can keep playing the scenario as long as they like.