Very good one !
Nice job on the parallax trick, this makes the game feel much bigger without breaking the GB limitations.
Altough I don't know how you could achieve the moving ceiling of the second level on a real GB. Does the GB have horizontal blank interrupt ?
Anyway, impressive amount of work in such a small time !
Yes it does! ; 3
You can see it being done in games like Ninja Gaiden Shadow and TMNT Fall of the Footclan, among many others, and a surprising amount of European-developed GBC games actually use Hblank interrupts on every scanline to change the solid BG colour in order to pull off an Amiga-style gradient in the background, effectively creating a 2nd BG layer! (Though one that only displays vertical gradients, it was also done in a Goemon game by Konami, though to a lesser extent)
