Kaos
If you can find an arcade to walk though today, you'll discover a boring assortment of shooting games, dancing games, and of course, fighting games. They're all derivative of each other, and it's enough to make you long for the glory days of 1981, when designers weren't afraid to take a chance and inject a little Kaos into the natural order of things…
Gameplay: You are a cross between one of those weird little Amidar ducks and a clown. You're trapped in a vertical maze where the walls and floors move from side to side, and a mysterious force drops giant spinning coins that you must collect to advance to the next level. However, if you miss a coin and it drops off the bottom of the screen, it turns into a dragon which wants to eat you. To defeat the dragon, you must climb to the top of the maze and hop into a magical pyramid, which transforms you into a king, complete with cool crown, shield, and triumphant music. And if all of this isn't enough to keep you busy, if you touch the side of the screen, or drop through the bottom, you'll be violently electrocuted. And if that isn't enough, you must collect all the dragon-hatching coins without dying; die once, and you'll start the entire level over. Kaos may be the most aptly named game of all time.
Could be mistaken for: The second level of Zoo Keeper, or the anime classic Before Becoming The Dragon, The Coin Is Captured Splendid Search!