The Perfect Trap

After you've 1) Helped get the Locator Computer back during the mission The Theft, and 2) Obtained relics with Mali during your Adventure of the Starlight Island, Gale will ask key players, including you, in the town to gather for a meeting.

Go find Ack and ask him about a diagram of the All Source.

Ack will give you his sketch (a diagram for an All Source Model). Use it to build a model and bring it to Arlo. He will hold on to it until the rest of the plan is ready to go.

The final step is to make the trap. Obtain the diagram from the Research Center and construct a Trap Device. Bring it to Arlo.