The differences are mainly two: * Instead of the plain dark blue sky, the sky over Castle Britannia originally was overcast and it was raining. Only the lightning remains in the shipped game. * The whole last third of the intro with the Avatar's ship approaching the Serpent Pillars was totally different. It was much more animated; the Serpent Pillars rose from the sea, and many perspectives were different. This was all replaced with mostly static backgrounds.