The Observatory is the marines' eyes. It needs power and requires an Infantry Portal and an Armory.
Passive detection#
A built, powered Observatory reveals cloaked aliens (Camouflage, Shade cloak) and cloaked cysts and drifters within 22 m. Place one in each important forward room.
Scanner Sweep#
The commander can scan any spot on the map for 3 team res. A scan reveals everything within 20 m for 10 s, including cloaked units, and lets ARCs fire at what it reveals. Scans use the Observatory's energy, so spread them between observatories.
Distress Beacon#
For 10 team res, after 3 s every living marine who is not already in that room (exosuits excluded) is teleported to the Command Station nearest the Observatory. Use it to save a base from a rush. It is loud: aliens hear the alarm and know the marines are coming.
Phase Tech#
Researched here for 10 team res (45 s). Unlocks Phase Gates.