Halo Season 2 Explains The 1 Thing That Sets John & Other Spartans Apart From All Humans

Spoilers are ahead for Halo season 2, episode 7.

Halo season 2, episode 7, “Thermopylae,” finally reveals what sets John-117 (Pablo Schreiber) and his fellow Spartan-II soldiers apart from all other humans — and it stems from Dr. Catherine Halsey’s Forerunner twist from the previous episode. Natascha McElhone’s UNSC scientist has fallen from grace: the show’s sophomore season opened with Halsey being held captive by her replacement, ONI officer James Ackerson (Joseph Morgan), who subsequently arranged for Dr. Halsey to die during the Fall of Reach. Alongside John and former Spartan Soren (Bokeem Woodbine), Halsey survives the invasion, but the remaining Spartan-II soldiers aren’t too pleased.

The ending of Halo season 1 revealed a lot about Dr. Halsey’s nefarious intentions. Not only did she want Cortana (Jen Taylor), her A.I. construct, to take over John’s body and turn Master Chief into the ultimate, emotionless weapon, but the scientist revealed the unethical foundations of the Spartan-II program. As it turns out, Dr. Halsey traversed the galaxy and abducted young children for the program, leaving flash-clones in their place. Most of the young candidates didn’t survive the supersoldier augmentation process. Those who did harbor resentment toward their creator, especially as Halo season 2 unfolds.

Dr. Halsey Reveals The Connection Between Her Spartans & The Forerunners

The sixth episode of Halo season 2 sees Dr. Halsey and Kwan Ha (Yerin Ha) working together on Onyx. Following Kwan’s visions, the unlikely pair navigate a network of tunnels. Riddled with Forerunner markings, the site is “where it all started” for Dr. Halsey, who spent months toiling away in the dark. Now, Halsey’s daughter, Commander Miranda Keyes (Olive Gray), has taken up her estranged mother’s research efforts. With Kwan’s help, the mother-daughter duo unlock a cryptic Forerunner door, which leads to a lab. Before they enter, Dr. Halsey reveals more about Onyx’s secret Forerunner connection.

Dr. Halsey found DNA — both “theirs and ours” — at the ancient Forerunner site. This discovery prompted Halsey to consider the next stage in human evolution. Judging by Kwan’s cutting words, that next stage was the Spartan-II program. After unearthing the DNA strands on Onyx, Dr. Halsey searched the galaxy for people with that specific genetic code. That is, she wasn’t abducting children at random. So far, the Covenant’s “blessed ones” are few and far between, with only John and Makee (Charlie Murphy), a Covenant-raised human, fitting the bill. But Halsey’s reveal might change all that.

Halo Season 2 Hints At The Spartans Being Reclaimers

The revelation in episode 7 that the Forerunner site is a Library teases The Flood’s appearance in Halo season 3. In a similar vein, the connection between the DNA Dr. Halsey found on Onyx and her Spartan program hints at the fact that all the Spartan-II soldiers are actually Reclaimers. In the core canon, the term “Reclaimer” is used by Forerunner constructs to refer to humanity — the species the Forerunners passed their Mantle of Responsibility to. That is, like the Forerunners, the species with the Mantle is charged with tending to all life in the galaxy (via Fandom).

As a result, Reclaimers in the core canon are able to activate Forerunner technology, from the Halo Array to the Shield Worlds. This element from Halo‘s core canon aligns pretty closely with the TV show’s “blessed ones” concept, as humans like John and Makee are able to activate Forerunner tech, including the keystones. While Makee’s backstory is unclear, the Spartans were all hand-picked by Dr. Halsey because of their genetics. It’s possible that in the Silver Timeline only certain humans carry the Mantle of Responsibility, making these “blessed ones” the Halo show’s version of the Reclaimers.