ウソ800
A powerful gadget from [[Doraemon]]. Granted the user an ability that turns everything they say into a lie by manipulate the surroundings and causing an opposite thing to happen.

[spoiler]This gadget was used as a plot device to bring [[Doraemon (character)|]] back from the future during the final episode of series 2 "Goodbye Doraemon".[/spoiler]
lying potion 800