[@FlitterFaux] Credits is a "currency" you can earn through completing missions given to your team in IC (right now it's family day so no missions atm) or participating in Heroes of Beacon Contests and placing high enough for a contest- and very occasionally, the contest gives you free credits for participating. In the first page of the OOC, there's a Conference Doc that has info on what kinds of upgrades or things you could get with credits.

Another form of currency is Lien, but that reflects more on your character's wealth than anything.

EDIT: snow tl;dr'd this long-ass post below