Big Star Key

The Big Star Key refers to an unused model in Super Mario 64 DS that is a larger version of the Rabbit Keys. When collected in-game, it unlocks the doors to Princess Peach's Castle, similarly to the first Rabbit Key collected. However, it is possible this is a placeholder. Theories state that it was intended for an unused boss.

How To Unlock
There are several theories as to how to find this key. These include:


 * Entering the Black Box.
 * Entering Peach's Balcony.
 * Catching the Purple Rabbit.

Rabbit King Connections
Seen in the supposed Purple Prizes magazine is a mention of a Rabbit King that must be encountered as a step to unlock Waluigi. It is possible this Big Star Key would be used when defeating the Rabbit King to unlock Waluigi's door. However, this would conflict with other Character Keys. Another theory states it is a Star Key due to Waluigi being the last character someone would unlock in 64 DS.

What It Unlocks
There have been several theories as to what the Big Star Key unlocks. These include:


 * The Black Box.
 * Peach's Balcony.
 * A 151st star.
 * Waluigi.
 * A playable Rabbit character.