The first Actraiser was a unique game, it had side-scrolling action stages interspersed with Sim-City-esque building stages. Which mostly means that if you want to get to the Big Bad at the end of the game, you've got a lot of work to do.
Or do you?
You could fire up the sequel, Actraiser 2, go to the Password screen, and enter this password
If you do, you'll be whisked away to the final battleground of the first game!
Where you can fight the final boss from that game while in the second one. Why would you do that? To see if you still have the chops to defeat it. What happens if you do?
Uhm... I don't know. I wasn't actually able to do that...
If you can, let me know!