During last year’s Halo: Nightfall five-part digital series, fans were introduced to Jameson Locke, a capable soldier and ONI Acquisitions Specialist sent to investigate Covenant activity on the planet Sedra. For Halo 5: Guardians, Locke has been promoted to Spartan and tasked with hunting down the fallen hero, Master Chief. Fortunately, Locke isn’t alone; he has handpicked a team of specialists at the top of their field. If anyone stands a chance against Master Chief and the rest of Blue Team (read about them here), it’s this new team of Spartans. Meet Fireteam Osiris.

The UNSC Spartan programs have a morally clouded history. The Spartan-IIs were kidnapped at the age of six and forced to train to become hardened warriors. The Spartan-II program left many trainees dead, injured, and emotionally damaged in its wake. However, the Spartan-IIs were necessary in winning the war against the Covenant.

In contrast, the Spartan-IVs seem like a wholly noble effort. The men and women in the Spartan-IV program have chosen a life of military service. They’re driven and often the best of the best in their respective fields. “If these were real guys, they would all be quarterbacks,” says franchise development director Frank O’Connor. “But they are ultimately people. So they’re not robotic, single-minded monsters like Tom Brady. They’re more noble, handsome, beautiful Russell Wilson-types in my estimation. And you can quote me on that.”

343 Industries compares the Spartan-IVs to Nissan Skyline GT-Rs: every aspect of their armor is computer controlled, and every tool they have is state of the art. While the Spartan-IVs have some biological augmentations, they are simple, lower-level augmentations that were not nearly as invasive as those the Spartan-IIs received. Out of the suits, most Spartan-IVs wouldn’t stand a chance against a Spartan-II, but thanks to their top-of-the-line gear, Spartan-IVs are theoretically as good as Spartan-IIs.

Next up we breakdown the characteristics of each member of Team Osiris: Locke, Tanaka, Vale, and Buck.

Jameson Locke: Locke is an ex-agent of the Office of Naval Intelligence, but he has recently started working for the United Nations Space Command as one of their newly minted Spartans. In spite of what fans might think based on the recent trailers, 343 Industries says that Locke doesn’t hold any animosity towards the Chief, but he’s been given a mission to bring him home, and Locke is the kind of guy who always comes through on his mission. Locke is a world-class man hunter; if you need someone tracked down, Locke is the guy you want to call.

Holly Tanaka: Halo fans were introduced to Tanaka in Dark Horse’s ongoing comic series, Halo Escalation. One of only 10 survivors after her home world of Minab was glassed during the Covenant war, Tanaka endured a three-year nuclear winter on Minab’s barren surface before being rescued and joining the UNSC Army. Later she volunteered for augmentation and training as a Spartan-IV soldier. Tanaka comes from African and East Asian descent, and her time surviving on Minab has given her a will to fight and survive no matter the cost.

Olympia Vale: At the end of the war with the Covenant, the Navy needed specialists to help bridge the gap between Humanity and the Covenant. One of the most important players in this political game was Olympia Vale. A post-war political liaison with the Sangheili, Vale was a child prodigy who is very skilled in language, and has learned to speak many of the Covenant’s dialects. Vale is a fairly new character for the Halo universe, so little is known about her currently. She will be a key player in the upcoming Halo: Hunters in the Dark novel, so fans will learn a lot more about her when the book releases on June 16.

Edward Buck: Likely Fireteam Osiris’ most recognizable face, Buck is played by popular actor Nathan Fillion (Firefly, Castle) and was first introduced to fans in Halo 3: ODST where he helped lead a team of ODSTs on a covert mission during the Covenant invasion of Earth. Buck has trained in all manner of armed and unarmed combat and served on the front lines for two decades, participating in several black ops and wetwork missions. It was once said that if Buck were any better he’d be a Spartan. Halo 5 proves that he must have gotten better, because Buck has now graduated the Spartan-IV program. However, Buck still wears his old ODST helmet that he's comfortable with.

(Learn more about Master Chief's family in our profile on Blue Team.)

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