1- Eustass Kid is one of twelve pirates who are referred to as the “Worst Generation”. Sometime during the timeskip, his bounty was raised from 315,000,000 Berries to 470,000,000 Berries.
2- Kid aims to be the most violent pirate out there. He does so as an act of rebellion towards the scum that rule the world. He rules over his crew with evil charisma. Unlike Luffy, when Kid speaks of his experiences in the Grand Line, he mentions killing everyone who dared to laugh at him and his dream to find One Piece and become Pirate King.
3- Like Luffy, Kid has another member of the Worst Generation in his crew. Kid and Killer are childhood friends. Together they formed the Kid Pirates.
4- Eustass Kid’s surname and name was taken from two real-life pirates. The surname Eustass was taken from 13th century French pirate and mercenary, Eustace the Monk, and the name Kid from 17th century Scottish pirate and privateer, William Kidd, who was also nicknamed “Captain”.
5- The water torture that Kid and Kamazo were subjected to in the Wano Country Arc is a version of the old Japanese torture and execution method known as tsurushi or “reverse hanging”.