#8 – Koby
Koby is a Marine Captain who trained together with Helmeppo under Vice Admiral Garp’s supervision. He is currently a member of the Marine special forces unit SWORD. He was formerly an involuntary cabin boy for the Alvida Pirates until he was liberated by Luffy.
#7 – Vergo
Vergo was one of the four elite officers. At age 26, he enlisted in the Marines under Doflamingo’s orders. Having spent 15 years ascending the ranks, he nevertheless was an enemy to the organization from the beginning, as he assisted Doflamingo in criminal activities by abusing the privileges as a high-ranking Marine officer, as well as passing off vital information and coverups. He was dishonorably discharged when Smoker reported him to Sakazuki.
#6 – Diez Barrels
Some time in the past, Diez Barrels was a Marine Officer but left to pursue piracy. His reason for leaving remains unknown.
As a pirate, he gained some infamy and acquired the Ope Ope no Mi. He made a deal with the Marines to exchange the fruit for a large sum of money, however, Rosinante stole the fruit and gave it to Law. Barrels was later killed by Doflamingo.
#5 – Caesar Clown
Caesar Clown used to work with Marines as their scientist. During the Dressrosa Arc, Donquixote Doflamingo declared Caesar to be his direct subordinate, meaning Caesar was a de facto member of the Donquixote Pirates. He also took part in a rebellion against Big Mom together with Fire Tank Pirates and Straw Hats.
#4 – Donquixote Rosinante
Donquixote Rosinante was the younger brother of Donquixote Doflamingo. He became an Elite Officer of the Donquixote Pirates, serving under Doflamingo under the codename Corazon.
The truth, however, was that he was a Marine Commander, working undercover in order to stop Doflamingo. He was found out by the former Corazon, Vergo, and was executed by Doflamingo 13 years ago.
#3 – Shiryu of the Rain
Shiryu of the Rain was the Head Jailer of Impel Down until he was imprisoned for his excessive violence towards the prisoners. For that, he was sentenced to death and put on death row in Level 6. Currently, he is one of the Ten Titanic Captains of the Blackbeard Pirates as captain of the Second Ship.
#2 – X Drake
X Drake is the Captain of the Marine Secret Special Unit SWORD. In order to go undercover as a pirate, he publicly defected from his position as rear admiral and founded the Drake Pirates. He is one of twelve pirates referred to as the “Worst Generation”, and prior to the two-year timeskip had a bounty of 222,000,000 Berries. Currently, he and his crew are affiliated with the Beasts Pirates led by Kaido. X Drake serves as one of the crew’s Headliners and is one of the Flying Six, six of the strongest Headliners. His treachery was eventually uncovered, however, leading him to attempt to ally himself with Monkey D. Luffy.
#1 – Kuzan
Kuzan, better known by his epithet Aokiji, is a former Marine Admiral and the first one to be revealed. He was nominated by Sengoku for the position of Fleet Admiral. However, after losing the position to Sakazuki, he resigned from the Marines and affiliated himself with the Blackbeard Pirates. It is unknown what standing he has with the crew, but some like Jesus Burgess are not so quick to trust him because of his past as a Marine, but Blackbeard pays it no mind.