I think you people have the right idea, but for the wrong reason.
Kolossos is the root meaning, large, huge. Yes, the Colosseum was a place where people fought, but it was named that because it was huge.
So yes, I think it could be PvP, but because the title alludes to the SIZE of the Issue, not the place to fight. It's a double entendre, me thinks.
Very nice work