Star Rod (Paper Mario)

The Star Rod is a magical rod that can make wishes come true. It is stolen from Star Haven by Bowser at the beginning of Paper Mario and used to grant all of his evil wishes. Using it, he easily defeats Mario by making himself invincible. Mario and his partners must save the seven Star Spirits to deactivate the power of the Star Rod.

According to Russ T., who lives in Toad Town, the Star Rod was created by ancient magic long ago.

In the final two battles against Bowser, the Koopa King would use the star rod to make himself invincible or to recover HP. After freeing all of the Star Spirits, Mario can use the star beam to cancel out the Star Rod's effects when Bowser makes himself invincible.

Trivia

 * A similar item with a more or less similar appearance appeared in the Kirby series first. It also has a similar role. It's unknow if this was made on purpose.