Needs a bit more work IMHO
This is quite a decent game but there are some things i want to point out:
1. I just felt that the controls were sometimes laggy, maybe its my computer but.. anywyz...
2. 1 major problem is that the cannon cannot shoot UP which made it a hell of a lot harder to play
3. The music after it looped a few times got a bit tedious
I think its great how you captured the essence of Metriod though, well done!