... because it is, simply, the best game EVER on Amstrad CPC!
Except, perhaps, for the music! ^_^
I saw what you did there
Anyway, the game is an achievement for the CPC.
We had many ZX ports in the past (like the MSX) and many games that didn't show what this machine could do.
We also had/have the reputation of the worst scrolling 8bit and the slowest one in games.
As I mentioned before in this post, this game except of the scrolling has also great physics for a hardware with an 8bit cpu and no fancy hardware like the atari 8bit line or the brown one.
If you consider now that it looks and feels like the amiga, better than the SNES and that it runs on a Falcon then yes, it is a miracle.