Crystal Ball
From Starfy Wiki
Crystal Balls (Japanese: すいしょうだま) are objects in Densetsu no Starfy 4. They are found in Degil's Castle, with the exception of one in Thousand Year Hill that teleported Starfy to Stage 7-1.
The Crystal Balls in Degil's Castle are found with panels marked with Degil's face. If Starfy or Starly hits it with a Star Spin, it will mark the correct path for them to follow. If Starfy or Starly follow the correct path it will fill the panels and make them passable with any path. If Starfy or Starly follow the wrong path, an 'incorrect' sound effect is played and Starfy or Starly are dragged back to the Crystal Ball.