From the Super Mario Wiki
Slow Dice Blocks are a type of special Dice Blocks appearing in Mario Party 9. They are similar to normal Dice Blocks, but are completely gold in color and the numbers are blue. The numbers on the Dice Block will scroll by slowly, allowing the user to roll a specific number easier. They work similarly to the Slow 'Shroom Orb and the Slowgo Candy, the only difference being that the player should hit as soon as the number the player wants to get appears for the player to get the desired effect. The player must be careful not to shake the Wii Remote, making this Dice Block spin faster and get bigger, thus the numbers will scroll faster. The hardest the player shakes the Wii Remote, the fastest the numbers scroll. Slow Dice Blocks can be obtained by landing on a Dice Space, a Spin Space or from a Toad House. Another way of obtaining a Slow Dice Block is for the player to be in last place when the "Almost There!" event occurs.
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