Prestige

Prestige is used to "buy" items and rooms for your supergroup's base.

When you click on the Super button, it brings up the list of people in your SG. In the upper right corner is a button that says, "Enter SG Mode"

Click that.

You will earn Prestige as well as influence/infamy when you defeat enemies and complete missions. Around lvl 25 you will start earning less influence/infamy, and around 35 you will stop earning influence/infamy at all while in SG mode.