Muumit ja Suuri syysjuhla (The Moomins and the great festival in September) is the eighth Moomin computer game. It was released in 2007.

The game is one of the Moomin computer game in which the difficulty level can be selected, although the difficulty levels have now become one more. The game is also the first Moomin game, where you can choose in which language plays (Finnish or Swedish). None of the Moomin'a familiar voice actor does not appear in the game.

Player's mission is to help Muumipeikkoa annual Autumn celebration arrangements. But before the formal arrangements are in place, and has a lot to do Moomin needs all possible assistance to cope with it. Variety of functions, which always gets a prize or something being good for is plenty to celebrate: Muumipeikon punch machine (which is out of order), Moomin Papa duck guidance, Hemulen kukkavaja, Snork freight sorting, Tiuhdin and Viuhdin darts, Sam and his friends to help over the water, Tiuhdin and Viuhdin gem game (which may play a role after the Samu-), magician guessing game, and Little My quiz.

All tasks must be done in order to finally begin festivities.