Almost all CommSphere scenes are optional, though brief use of them is required at the beginning of Chapter 4 as the party checks on what's happening with Spira's leaders. One of the CommSpheres first appears on the bridge of the Celsius toward the beginning of Chapter 3 and Shinra explains that it can't be used until he sets up a Spira-wide network on the ground. He then does so as the party visits various areas during Chapter 3. If a location is not visited during this chapter, then a CommSphere is not placed there. Shinra also develops a mobile CommSphere that can be sent into remote areas.