Barrell Caskett is the adoptive "grandfather" of MegaMan Trigger, and a character in the Legends series of Mega Man games.
Barrell Caskett's first major adventure was with his long time friend Verner Von Bluecher when 30 years ago, they became the first explorers to make it to Forbidden Island and return alive. All other attempts before and since resulted in that explorer's mysterious disappearance; including Barrell's daughter and son-in-law Matilda and Banner ten years ago. In Legends 2, Barrell reluctantly teams up with Bluecher again to try to return to Forbidden Island again. Barrell has also served as a professor, with Kattelox Island Mayor Amelia being one of his former students. Today, Barrell raises his granddaughter Roll and adopted grandson MegaMan and helps and supports them during their adventures whenever he can.
Barrell is similar to Dr. Light
from the Classic Series in the sense that he too serves as the parental figure for MegaMan and Roll (even though he's their grandfather). However, he is too old to fight for himself and is not nearly as mechanically savvy as his granddaughter, so he serves mainly as a supporting figure during Mega Man and Roll's adventures.