Barrel Malum. 

When Barrel was human, he was also one of the unlucky ones due to the parents that he was born to like his pseudo-siblings Lock and Shock; however, unlike the other two, Barrel wasn't an only child. Barrel not only faced anger and hatred from his parents but also from his elder brothers, this soon led to Barrel being nailed into a fishing Barrel on the boat that his parents made their living on and then thrown into the sea.

Barrel was the final of the trio to appear in Halloween, dressed as a skeleton that the sea had turned him into. Due to the mischief that he soon thrived around, now that he could be his true self; Barrel was also held at arm's length by the people of Halloween which led her to become an apprentice and minion of Oogie Boogie and a younger sibling to Lock and Shock who surprisingly treated him better than his human siblings.

After the events of the Nightmare Christmas, and with the move of Halloween into Auradon, Shock and her 'siblings' were banished to the Isle along with the demonic being that they had previously betrayed. The magic twisting their auras and forcing them to age at half the time that they should have. Left to work under the man that made their parents look like saints, the trio were 'employed' as his enforcers and became as feared on the Isle as they were in Halloween.

 Verses 

Isle of the Lost: When every state was pulled into Auradon, the King did not expect the land of Halloween to be pulled into existence along with it; and so the majority of Halloween Town was sent to the Isle where Oogie Boogie took over his own chunk of territory and used his ‘boys’ to enforce his rules and regulations.

Auradon: The trio was offered a spot in Auradon, it was a way for Halloween to try and make up for sending the three nine-year-olds to the Isle of the Lost with an abusive demon, and a magical barrier that changed their aging so that they aged one year, every two years that they lived upon the Isle.

None of them liked Auradon, it was the exact opposite of the home they remembered, they would have preferred the Isle over the bright and sunny places of Auradon