What would be the ultimate CoG or HG crossover?

I’ve wondered about this quite a bit.

What would be the most awesome crossover gamebook featuring characters from different CoGs or HGs?

And do you think we’ll ever seen one? I know it would be hard to execute, but it seems like you could possibly capitalize on different fan bases and audiences. Plus it could be awesome! I’m guessing because of IP issues and general flexibility requirements, a HG version would be more feasible. Any thoughts?

There is already a thread for this topic/conversation. Please resuscitate that rather than creating a new one.