Not all of Millennium's creations had been vampires. The perennially mute Captain, the greatest of Millennium soldiers and highest amongst the Werwolf elite force, is a prime example of this-always seen at the Major's side, first seen protecting him against Hellsing operatives in 1944 Warsaw, in the Order 666 base. He squared off against Walter C. Dornez when the young Hellsing servant threw a knife at the Major. The Captain simply caught it inches away from the fat man's face, and his supernaturally toughened flesh managed to resist the cutting power of Walter's monofilament wires, allowing him to bring down the young Hellsing servant and choke him before the Nosferatu Alucard attempted to stop him. The Captain simply kicked off Alucard's top half, forcing him to back out and to focus in pursing the Major. Alucard even remarked how he believed "his kind" had been made extinct long before, and took moments to taunt him by barking like a dog and locking Walter and him in the Order 666 compound officer dining room before leaving for the Major. In spite of this series of events, the Major, the Captain, Rip Van Winkle, Walter and Alucard all survived the destruction of the Order 666 camp through still unknown circumstances. Later that year, based on a picture of him, he and the Major still were in the Ardennes on 17 December, participating in the Battle of the Bulge massacre, and remained there until that month's 20th.
Along with all the others participating in the Millenium Projekt, he would leave Europe and go into hiding for decades, as the Doctor continued to pursue the perfect method of building a vampire army, ultimately completing the batallion of a thousand undead soldiers. The Captain would rise through Millennium's ranks until he was named leader of the elite Werwolf team, a special cadre of vampires (he was the only remaining natural werewolf) with special powers, trained to be the Projekt's most powerful soldiers, to serve as lieutenants of the batallion. When the elder SS generals attempted to shut down Millennium, considering they had failed (not knowing about the vampire surgery development) the Major ordered his forces to kill the older military men and assumed leadership, becoming the de facto ruler of the Batallion, with the Doctor and the Captain as his scientific and military aides, respectively.
The silent killer would not meet his old enemy, Walter, until the massive invasion of London orchestrated by Millennium. He appeared in front of Integra Hellsing's car, blocking the fastest route to Hellsing HQ, and forcing a confrontation between himself and Walter. He proved to still be capable of holding Walter's wires, and both ended in a stalemate, until Millennium's main airship Hindenburg II loomed over them, and took Walter away, whether by force or willingly. He later assisted the main battle between the Millennium soldiers, the Iscariot paladins, and Alucard's familiars, representing the Army of Hellsing, and left to allow for the final battle between Alucard and Anderson. Later, to dissuade Iscariot operative Heinkel Wolfe from further pursuit, he shot her, heavily scarring her face, and promptly gave her a first-aid kit and gestured her to stay out of the way, implying a respect for a fellow warrior.
He would not be seen again until Seras Victoria and Integra Hellsing reached the downed Hindenburg II to crush the remnants of the Millennium invasion. Seeking to duel with Seras, he pointed Integra to the command section of the zeppelin to get her out of the way and have a fair joust. Both proceeded to brutalize each other, in a battle that took both of them to the main hangar of the Hindenburg II, a massive room filled with countless valuables and WWII memorabilia. Seras attempted to impale him with the solid darkness awakened within her, but the Captain proceeded to shrug off the attack by dissolving in a cloud of mist and taunted her by standing atop the mass of darkness, unharmed. Both continued their reckless attacks, displaying massive power. When the Captain was about to prevail, Seras knocked him to the floor and held him in place by biting down his leg. This gave Pip Bernadotte, her new familiar, time enough to grab a concentration camp inmate tooth with a silver core and pierce the werewolf's heart. Upon doing so, the Captain burst into flame, much like the other slain Millennium operatives, and dies laughing, as his dogtags fell to the floor and break. Given how Seras held him down, it is likely she absorbed his soul, making him her next familiar.
The Captain, as the last natural werewolf, displayed massive amounts of stamina, raw strength and the capability to regenerate immense amounts of damage by shifting into his mist shape and returning to physical shape. He had two alternate shapes: a half-man, half-wolf creature, and a monstrously huge wolf. As well, he handled twin Mauser guns with tremendously long barrels, and a large combat knife, which he never got to use. As well, his flesh was incredibly tough and resisted Walter Dornez's deadly wires, only bleeding. His resistance to pain was also highly remarkable.