Much more concrete, by the way, is That Goddamn Sign in the Arcadion art is in the actual arena... in orange, where it suddenly looks a lot less like everyone's main suspect.
Alongside some of the same ads we've seen in Solution Nine, and text that seems to be a
real jacked up Ancient alphabet; that says the name of the first boss, Black Cat, so that's probably the fighter promos. The sign we know doesn't resemble Black Cat themselves in any meaningful way, though; I could maybe buy the lower half as resembling their claws or their fur coat, but the head doesn't line up. So that suggests that the symbol is for the Arcadion itself, it's like the 'WW' logo for the WWE. (I had a brainwave there and tried to find the Ancient letters for 'Arcadion' in it, but no luck.)