Do the Mamba's have the same weight block?
I think I read somewhere that Gamebreakers don't meet USBC specs or something like that but they are legal because they came out before the spec rulle change?
Once balls are approved, they're approved forever because they met the standards at the time of their creation and manufacture. Whether they meet them now or not is irrelevant.
Mamba's are made by 900Global/AMF.
Gamebreakers are made by Ebonite.
Totally different corporations.
They won't and can't have the same core.