This is certainly the oldest project I've completed so far, having been in the making for over four years. I remember a hard drive crash being responsible for the initial suspension of the project, which I had to restart several times to finally see it through.
I can honestly say that this is one of the few NES games out there that are actually a real challenge to map properly. I mean, the game engine probably changes with every stage, with things like parallax scrolling and just plain horizontal and vertical scrolling coming and going on the whim of the game coders. This game is also probably the one that made me try my best to 'hack' the camera position through memory cheats to capture those areas that you simply cannot reach during normal gameplay.
This came in handy in mapping the full vertical height of
Level 5 - Surf City since vertical scrolling is normally automatic and can't be controlled. It was also instrumental in finally revealing to the world what exactly was located above the stating point in
Level 11 - Clinger-Winger and a nice little tidbit that isn't visible on the final map, that the layout for
Level 13 - Armageddon is actually located in the empty space under that same starting point (they just change the palette for that part but you can clearly see that it uses the same tilesets). I remember guessing a lot during my earlier projects to fill in empty space but I've been trying as much as possible to avoid that and so far, I'm pretty successful.
The only stage that was a real challenge to render is of course
Level 12 - The Revolution and I can say it's one of the individual maps I'm the most proud of. And funny enough, it allowed me to use what little knowledge I retained from high school trigonometry to achieve the best rotation possible (the game itself is actually a few pixels off for some angles). It took a long time to assemble despite using a ton of templates in MS Paint to easily paste everything in the correct position as quickly as possible, but I think the final result was worth it. I personally would have made the rotation much smoother than it ended up being but then the file size would have been even more horrible (it's already 4.8 MB big) and it would have taken 4 or 8 times longer to do! I'm only human you know, and even I'M not that big a masochist.
I'll also admit to having never made it past the final race in
Level 3 - Turbo Tunnel on a real NES back in the days when the walls start coming at you unannounced at breakneck speed. Gotta love those savestates