The Book On Bad

The Book On Bad is a supposed collectible, similar to the Ghoul Medal in nature, in Super Mario 64 that can be added into the game as a hidden collectible by the Personalization A.I. It is supposedly a book written by Bowser and his army, presumably on being evil. It was first mentioned by a Toad in this dialogue:

"Wow! You already recovered that many Stars? Way to go, Mario! I’ll bet you’ll have us out of here in no time! Be careful, though. Bowser and his band wrote the book on “bad.” Take my advice: When you need to recover from injuries, collect coins. Yellow Coins refill one piece of the Power Meter, Red Coins refill two pieces, and Blue Coins refill five. To make Blue Coins appear, pound on Blue Coin Blocks. Also, if you fall from high places, you’ll minimize damage if you Pound the Ground as you land."

It is believed this may be a reference to the collectible, though similarly to the Ghoul Medal, some say this is just figurative speech.

How To Obtain
There are several rumors on how to obtain the Book On Bad. These include:


 * Defeating a golden Bookend. The Bookend will drop the Book On Bad.
 * Punching a specific bookshelf a specific amount of times, causing the Book On Bad to fall out of the bookshelf.
 * Beating a hidden Bowser level. Beating the Bowser boss fight will make him drop the Book On Bad.
 * Opening a hidden room in Princess Peach's Castle containing the Book On Bad.

What It Unlocks
The Book On Bad can unlock several things. These include:


 * A secret ending.
 * A new Bowser level.
 * Nothing.
 * Appearing on the save file as an achievement.
 * A new floor of Princess Peach's Castle, most commonly the 4th Floor.