His big claim to fame was his exploration of the Forbidden Island 30 years ago with his partner, Verner Von Bluecher, and their subsequent return. In all of recorded history, they were the first and only people to successfully complete the expedition - everyone else who tried simply vanished.
During other parts of Barrell's career, he visited Kattelox Island and befriended the mayor. Later on, he was exploring the Nino Ruins when he came across the diamond stasis field where he found the baby he named MegaMan Volnutt. Taking MegaMan back with him, he raised him along with his granddaughter, Roll, after her parents disappeared trying to explore Forbidden Island.
Years later, Barrell was retired but still assisting MegaMan and Roll in their adventures. Their airship, the Flutter, crash-landed on Kattelox Island, and they had to go into town to try and find repair parts. There, Barrell was reunited with his old friend, Amelia. He aided the two Diggers when the Sky Pirates attacked and supported MegaMan during their next outing, when Barrell reluctantly agreed to try and explore the Forbidden Island once more. Again, he served in an assistant's capacity to Roll and MegaMan, providing them with advice and general maintenance of the Flutter.
- Barrell's character is akin to Dr. Light from the Classic series in that he's quite the parental figure to MegaMan and Roll (even though he's their grandfather). Also very much like the old doctor, he serves in a supporting role, helping his grandchildren from the sidelines.