'Mario Kart Wii' has had a secret Mission Mode on it for nine years.
A YouTuber, who goes by the tag MrBean35000vr, has discovered there are five options in the games code of the 2008 title's main menu rather than the four which players can see when they start up, and he has shared a video about his findings.
Once accessed, the sub-menu features eight yellow buttons without text on which allowed him to play some sort of secret game, which he says is "very similar" to Mission Mode in 'Mario Kart DS'.
He says in the video: "I just happened to notice there seems to be five links away from this screen.
"After some considerable effort I managed to get this hidden screen to load.
"The menus for Mission Mode have no available text, but the game is trying to load them; they've simply been erased.
"Similarly, a massive file that would've contained mission parameters is not present, and without it, the mode can't start - unless you simulate its existence, which is what I did."
In 'Mario Kart DS', Mission Mode feature several challenges and the YouTuber has found something similar in 'Mario Kart Wii', where the tasks include defeating enemies, performing wheelies and collecting items.
The racing video game was launched on the Nintendo Wii in April 2008 and features several classic characters, such as Super Mario and his plumbing assistant Luigi.
'Mario Kart DS' dropped in November 2005.