Crystal Ball

The crystal ball is a, well, crystal ball that has been featured in many games throughout the Mario series.

It was first seen in Super Mario Brothers 2. Birdo spits it out after being defeated, and lifting it opens the door to the next level.

It was later seen in the Paper Mario series, but as the main magic tool for Merlon's family.

It was seen again in Luigi's Mansion, used by Madame Clairvoya to see the furture, and other things.

It was seen once more in Mario Party 6, in the Seer Terror mini-game.