Mario Kart Series
The Golden Mushroom is a power-up in the Mario Kart series. Once activated it gives the player unlimited speed boosts for a short period of time. In Mario Kart:Double Dash!! it was Toad & Toadette's unique item.
In the Mario Party games it allows the player to roll three dice blocks on their turn. It awards 30 coins for a triple number and 50 coins for roll of triple sevens.
Mario & Luigi: Superstar Saga
In Mario & Luigi: Superstar Saga, the Golden Mushroom is used as a healing item, restoring both HP & BP. There are only five Golden Mushrooms in the game. Later games replaced the golden mushroom with Star Candy.