The killer game that pushed the Game Boy into the upper reaches of success was Tetris. Tetris was widely popular, and on the handheld format could be played anywhere. It came packaged with the Game Boy, and broadened its reach; adults and kids alike were buying Game Boys in order to play Tetris. Releasing Tetris on the Game Boy was selected as #4 on GameSpy's "25 Smartest Moments in Gaming".
The original Game Boy was the first cartridge-based system that supported more than four players at one time (via the link port). In fact, it has been shown that the system could support 16 simultaneous players at once. However, this feature was only supported in Faceball 2000." (Wikipedia)
Download Nintendo Game Boy No-Intro 20090924 Set:
Due to broken link the upload has been replaced with the latest set.