Play around with your badges.
If you have more than 1 badge, go to your Trainer Card and open your badge collection and do these 2 things:
1: Tap your badge with the Stylus to hear metal sounds.
2: If your badge looks rusty and dark, rub it with your Stylus to make it shiny. While you do, you'll see shiny stars gleaming (Max. 4) (I think).
We have more cheats and tips for this game here, Pokemon Platinum cheats
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