I lost many days to Kid Chameleon back in the day...not that great of a game but I have fond memories of it and sometimes run through it once in awhile on an emulator.
I actually made it to the final level several times...I think it was called The Final Marathon, and it was very, very, very hard. KC is a pretty damn hard game as it is, but the final level takes it to a whole new level, they really didn't want you beating it. I think I could make it there with lots of lives and continues remaining and use every single last one up trying to beat that bastard of a level, holy shit was it unfair. Didn't beat the game until I got a Game Genie. Apparently there's also a warp in the first level which takes your right to the final boss but I wouldn't learn about it until like 10 years later.
There were also certain routes you could take which would lead you to very difficult levels, some of them I could never beat so I would have to plan my route out to avoid them. If I made a mistake and took the wrong path, well, better luck next play session!
Anyone remember "Bug" for the Saturn? I thought that game was so awesome back in the day because the perspective changed at certain points, it was the best 3D we had before SM64 came out! Looking back, good god was that a bad game.