|Nicknames||The Masked Noble|
|Manga debut||Yu-Gi-Oh! 5D's Ride 9: "The D1 Grand Prix Begins!!"|
Adolf Mueller is a character from the Yu-Gi-Oh! 5D's manga. He is a finalist in the D1 Grand Prix.
Not much is known about Adolf's past, other than he apparently suffered an embarrassing loss to Jack Atlas on his path to become King.
Adolf was present at the D1 Grand Prix opening ceremonies where he watched Rex Goodwin's introduction to the tournament. When Rex mentioned the contestants had to break through a wall to win, Adolf questions what he meant, shortly before Jack bursts into the stadium.
Although Adolf's Duels weren't shown, he made it to the tournament finals and was shown on the cruise travelling to Saiko Island for the finals. When Lazar explains the Duel Zodiac, Adolf questions whether a Duelist can use a Star Ticket value of more than 12 to enter the finals, which Lazar informs him that he can't. He was later shown to have obtained the Level 3 Star Ticket by defeating Tiger Eyes, but he lost it to Admire Derby..
Lazar reveals to Andre that he defeated Adolf and sealed his soul within a "Soul Prison" card.
No cards in Adolf's Deck were shown.