Mario & Sonic at the Olympics hidden characters found

While the character selection in Mario & Sonic at the Olympic Games already has a wide variety of characters from both the Nintendo and Sega universe, hidden away in the games coding is even more. Unused characters include the sexually ambiguous Birdo, Donkey Kong, Silver and Jet. Other characters such as Shy Guy, Toad, Cloudy and Cream are also in the game but are incomplete. Its not known whether these characters were never added due to time constraints or just beta testing. Source: Sonic Retro