Bowser???

Bowser??? is a boss in the game Paper Mario. He is controlled by the Koopa Bros., but is actually weaker than the Koopa Bros. themselves. It only has one attack: hitting Mario with its hand. It has more defense than most enemies, but Bombette can bypass its defense. After being defeated, Bowser??? will break into pieces and fall into the prison cell used to hold the Bob-ombs (which the Koopa Bros. also eventually fall into). A picture of Princess Peach can then be seen on the bottom part of it. Bowser??? seems to be made out of cloth and what may be cardboard or metal, and its purpose was to fool Mario into thinking that it was indeed the Koopa King (and further to create the illusion that it was invincible, as the real Bowser was at the time).

In the ending parade of Paper Mario, Bowser???'s remains have been transformed into a float for the Koopa Bros.

A similar character called Mecha Bowser appeared in Super Mario Sunshine. Mecha Bowser, like Bowser???, was also a poorly-made Bowser robot, though it was far larger.

Paper Mario Stats and Tattle Information
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 * HP: 10
 * Attack: 1
 * Defense: 1
 * Location: Koopa Bros. Fortress
 * Tattle: Bowser...? But he looks kind of...lame. I mean, he's lame anyway, but... Does Bowser really look like this? I always imagined him looking, well, a lot scarier.

Trivia

 * The background music used in the fight with Bowser??? is a remix of Bowser's theme from Super Mario Bros. 3.