Nemesis has written
Later as i think
If you noticed, in '90 you can found a weird catridge, Tank 1990 (Battle city hack), there is a ship so you can go trough water & pistol item, pistol=3 star + you can remove grass. I ripped them & gaved those sprites to Blazz, but he got many work with engine. You can search for this rom now & play with some emulator :3