If you are unable or unwilling to play in multi-player, though, then what you want... that's not really possible to do in single-player. You are controlling one or the other and you will choose the winner. At best you flip a coin and decide who wins.
If only there were some mechanism by which a random outcome could be determined, perhaps weighted by various factors including a complex statistical system and rules for resolution ... like in every RPG you've ever played ... perhaps exactly like the one that
already exists in DOS2 ...
This is very simple gameplay, nothing complicated or difficult about it.
So can I assume that you've written up some source code or even pseudocode which can handle it?
I'm not a programmer, but if it's already possible to do this
right now in DOS2, it shouldn't be that hard to do it right now in DOS2. Call me crazy.