Nintendo has published plenty of classic puzzlers over the years, and Dr Mario - the NES and Game Boy game now remade in Luigi's image for Wii U - is widely considered to be one of them. In truth, it's probably most fondly remembered for its soundtrack, by Hirokazu "Hip" Tanaka, the guy Nintendo would call upon to compose a catchy melody or two whenever Koji Kondo was busy. Its main theme is the sort of tune you mightn't be able to recall from memory, but after about five seconds you'll be humming along to it, before spending the rest of the day trying to extricate it from your brain.
Earworms aside, I'm not convinced Dr Mario is all that great a puzzle game. It arrived at a time when Nintendo spent as much time retooling existing ideas as coming up with its own. In all likelihood, then-president Hiroshi Yamauchi wanted another Tetris to cash in on the roaring success of Pajitnov's masterpiece, and Gunpei Yokoi's match-four variant happened to fit the bill.
While it's hardly Yokoi's finest hour, there is a certain purity to its design. A medicine bottle is infested with more irritating bugs than your average Techland game, and it's your job to get rid of them by dropping coloured capsules onto their heads. Line up four objects of the same colour, horizontally or vertically, and they'll be removed from play, whether they are bugs or pill halves or both.