Are these villains, heroes, or non-affiliated superpowered NPCs?
The point about all the sports teams (as well as the local hero team) being black and gold was that in Pittsburgh, the heros would be all in black and gold. The villains...well, Pittsburghers tend to hate the Cleveland Browns, Cincinatti Bengals, Baltimore Ravens, New England Patriots (for the NFL), and...the rest of the sports, well they get a little cloudy, but the majority of the city isn't as passionate about hating other teams in those other sports. I've noticed that even NON-FOOTBALL and NON-SPORTS fans still will tell you how much they hate the Steelers' rivals. Very bizzare.
However, the anthropologist in me digressed. The point was that the black and gold theme is always reserved for the city's heroes. Pittsburgh centric villains would gravitate towards purple, orange, and maybe greens.
Note: Back in the day, when Pitt was an NCAA football or basketball powerhouse, West Virginia, Notre Dame, Miami and Penn State where the most hated college teams. The last few years (at least pre-covid) I haven't noticed any college animosities at all (except West Virginia and Penn State who the GenXers and older still hate).