The cake is a lie.

- Doug Rattmann on his famous den in Test Chamber 17 16

Doug Rattmann has been proud to call Test Chamber Seventeen his home.

- Cave Johnson in his A.I. state

Doug Rattmann, also known as The Wall Scribbler and The Rat Man of the Den, is a character that was to appear in Portal but instead made an appearance in Aperture Science Business Magnet's Portal 2: The Stupidest Sequel of All Time - A Beginner's Guide and Walkthrough of Valve Software's Portal 2.

He is more immortal than Sburban Kizzsprite himself.