Myth Makers: Super Kart GP (Nintendo Wii)
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100cc class races
Win all of the cups in the 50cc class races.
150cc class races
Win all of the cups in the 100cc class races.
Drive through fence
If you hit the fence in Easter Land at a certain part you will go through it. Hit the end of the fence and you will do a huge jump.
Special ability
Beat the time trial for each character you want to unlock.