Doopliss

"I'm busy thinking of new pranks and stuff! It's not easy either! Now get lost! ..Of course you guys WON'T. No way you ninnies go away quietly, am I right?"

- Doopliss

Doopliss is a Duplighost who caused trouble at Twilight Town, turning everyone into pigs and stealing Mario's identity and teammates, leaving Mario nothing but his shadow. His base of operations is Creepy Steeple. To find out what his name was, the player had to find the Superbombomb and give it to the Shadow Siren Vivian. Vivian joined Mario and the two had to guess Doopliss' name, because as long as his name wasn't known Doopliss could continue to use his most powerful magic. The only thing Mario and Vivian were missing was the lower-case letter P, which Doopliss had hoarded in Creep Steeple's basement in protection of Doopliss's Parrot. After getting the letter P, they correctly guess Doopliss' name and Doopliss flees back to Creepy Steeple. While battling Doopliss, Vivian discovers she joined Mario (since he was a shadow, she was not aware she was joining the very guy she was ordered to defeat) and she takes a little time to think it over. Vivian decides to join the party for real, because Mario treated her a lot nicer than Beldam and Marilyn ever did. Upon defeat, Doopliss is unmasked, surrenders Mario's identity and teammates back to Mario and gives Mario the Crystal Star he deserves. He flees Creepy Steeple in humiliation and joins the Shadow Sirens later on. During his time with the Shadow Sirens, Beldam insists on calling him a 'freak in a sheet'. He becomes a lot nicer at the end of the game and pursues a career in acting alongside Flurrie. His only appearance is in Paper Mario: The Thousand-Year Door.

Creepy Steeple Battle

 * HP: 40
 * Attack: 4
 * Defense: 0
 * Location: Creepy Steeple
 * Tattle Number: 104
 * Tattle Log: This is the beast that's plunged Twilight Town into the depths of fear and despair. It enjoys turning innocent people into pigs.
 * Tattle: ...??? Wow, how totally bizarre... This thing isn't here. There's a monster in here that looks like this thing... But it doesn't have a name. It's apparently good at transforming itself and other things. Maybe it used that power to turn the villagers into pigs! This thing is a real jerk!

Palace of Shadow Battle

 * HP: 40
 * Attack: 6
 * Defense: 0 (1 if he transforms into Koops)
 * Location: Palace of Shadow
 * Tattle Log: A fiend who takes the shapes of Mario and friends, then attacks. Currently a member of the Shadow Sirens.
 * Tattle: That's Doopliss. He's a shapeshifter, and even turned into you once, Mario! He may turn into one of us and attack. When he does, he'll have our abilities! Hey, how do you think he became one of the Shadow Sirens? Isn't that...weird? How do you think he stands Beldam's abuse? You think he's all right in the head?

Trivia

 * Doopliss' name probably derives from a combination of Doofuss and Duplicate, or a play on the word Doop (slang term for tricking a person). It may also come from Duplighost, the name of his species.
 * Doopliss' Japanese name is Ranperu, which translates to Rumpel and comes from the fairy tale character Rumpelstiltskin, as both offer the same challenge: to have another guess his name.