Single Boss in Team Mode

[DivineWolf]

I was wondering if there was a way to set it so that you wouldn't face two duplicate boss characters at the end of team arcade/team co-op arcade. What I mean is, even though you face 2 on 2 battles thoughout team arcade, was there a way you could make it so that the last boss character (if you have it set up in this way), fights on his own, without it being 2 on 1 from the start of team arcade mode.

I put together a game where Onslaught is the boss char for it, but when it's 2 on 2 team arcade mode, I fight two duplicate Onslaughts. I was hoping someone could tell me if it could be done.