I've talked to the Doyles about Merlin in the past (the inventors), and they apparently programmed a 'bunch' of games for it. Only 6 were used in the first one. We didn't talk about Master Merlin for some reason (short conversation, focused on the original game and Wildfire Pinball), but I bet when the idea for a sequel came up, they just used some of the other things they already had... Minimizes R&D a lot I'd expect...
