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In Super Mario 64 DS, if a player obtains five Silver Stars or presses a Star Switch, then a Power Star appears in the crystal Sphere. If a Star Switch is pressed, the Star remains in the Sphere for a short time. When the Sphere is touched with a Star inside, it will break and the player will get the Power Star. In VS Mode, most of the Power Stars are found in Star Spheres, except for the ones in The Princess's Secret Slide.
The Star Sphere reappears in Super Mario Galaxy and Super Mario Galaxy 2 containing the Silver Stars, though its appearance is now more bubble-like.