I have no idea where the sixth and final big bad boss will be.
The others are dead, and we have all the gear to venture into the mist lands and fight whatever terrors lay there.
So far, completely overpowered NYC giant flying cockroaches.
For now, we are doing what we can within the limitations we currently have, to unlock the next tier of weapons and look for clues for the final boss.
The end may be nigh, but it could also take us a couple of weekends to knock out.