|Full Name||Chauncey, the Spoiled Baby|
|Biography||"He cries loudly and never sleeps through the night, but since he was born a ghost, this seems natural."|
|Heart Quote|| "Horsey... rocky... horsey..." (sleeping in crib)|
"Stay away!" (when "playing" with Luigi)
Appearances in video games
Chauncey first appeared in Luigi's Mansion, the launch title for the Nintendo GameCube. In the game, he is the third Portrait Ghost and the first boss of the game. He is the youngest Portrait Ghost in the entire game. He resides in the Nursery.
After Luigi sucks Lydia inside of his Poltergust 3000 at the Master Bedroom and goes out of the room, he hears a baby's cry from a room called Nursery on the left-hand side. Luigi goes inside of the room to find an infant named Chauncey sleeping in a crib. Luigi then find a rocking horse, and he rocks it to get the Chauncey's attention, according to the clue of Chauncey's heart. Chauncey then asks Luigi if he wants to play with him. Luigi gets a fright, and the door to the Nursery is sealed with spiky, white vines. Chauncey plays with Luigi by using his rattle to control his teddy bears to hit Luigi. Chauncey punches Luigi if he gets too close to him. While Chauncey plays with Luigi, he spots a giant ball on the ground; Luigi vacuums the ball onto his Poltergust 3000 and releases it at Chauncey. Chauncey loses his temper, claims that he had gotten an "owie", states that he hates adults and shrinks Luigi to be a smaller size.
Luigi is then relocated inside of Chauncey's crib. Chauncey appears and summons a lot of rocking horse, scaring Luigi. He then gives out a large cry, winks, and does a spin-punch in the air. The battle starts.
Chauncey uses his rattle to summon two rocking horses to charge at Luigi, both at the same time. He summons two horses again another time. Chauncey then summons a lot of balls to land inside of his crib that Luigi avoids; only a single ball remains inside of the crib. The player uses the C-stick to control Luigi to aim and release the ball at Chauncey. Chauncey is now vulnerable, given that his health is shown. Luigi then tries to vacuum Chauncey inside of his Poltergust 3000. Chauncey escapes the suction from the Poltergust 3000 since he cannot be vacuumed in one go. Chauncey then belly bounces around his crib. Since Chauncey has more of his health deduced, he summons his horses faster; Chauncey now summons his rocking horses three times instead of two times. After Luigi avoids the rocking horses three more times, Chauncey summons balls to fall inside of his crib again. Luigi has to use his Poltergust 3000 to aim and release the ball at Chauncey. Luigi then attempts to vacuum Chauncey in the Poltergust 3000. Chauncey is eventually vacuumed inside of the Poltergust 3000, and Luigi does a victory dance.
Luigi then turns to his normal size and finds a treasure chest next to the Nursery's door. He opens the treasure chest and finds a pink key which grants access to the second area. Luigi heads back to the Ghost Portrificationizer Room, one of the rooms of Professor Elvin Gadd's lab. Luigi empties his Poltergust 3000 by releasing Neville, Lydia and Chauncey into the Ghost Portrificationizer; the three ghosts are flattened by the machine, are electrocuted, and are all converted into paintings with either a bronze, silver or gold frame (which also affects the image). The frame and picture entirely depend on how many pearls Luigi had collected from Neville and Lydia and how long Chauncey was battled. Chauncey's number portrait in the gallery is three.
Chauncey is rematched in the Hidden Mansion for a second time. In the European and Australian versions of Luigi's Mansion, Chauncey now summons bigger rocking horses at Luigi that wave left and right as it charges toward Luigi. Chauncey retains his belly bouncing attack, except it's quicker than it was from the first battle.
Mario Kart series
Chauncey makes another cameo appearance in Mario Kart DS. He now appears inside of a framed picture at the Luigi's Mansion racetrack. Chauncey's portrait is identical to his gold portrait in Luigi's Mansion. Chauncey no longer has a cameo appearance in Mario Kart 7 because Luigi's Mansion only has Boo paintings that appear to have ghosts (presumably Boo) escape each painting.
- There are two glitches the player can do; the first glitch allows Luigi to suck Chauncey in his Poltergust 3000 in a single try, whereas the second glitch allows Luigi to walk behind the treasure chest just after Chauncey is vacuumed into the Poltergeist 3000. This allows Luigi to access various areas of the mansion.