In Guardians, after Blue Team defeated the Warden Eternal, Cortana tells them he is a single mind with a few million bodies. In the game, we fight only 8 bodies of his, which isn’t even beginning to touch the tip of the tip of the iceberg. He seems so determined to protect Cortana and make sure her goals are achieved. If you had to guess, do you think the Warden will appear in future media? If they do an Escalation-like follow-up to Guardians, would you except him to show up, or other corners of the media. And of course, do you think he will most likely be in Halo 6?
I certainly hope so. It’s terrible of 343i’s behalf to introduce this new mechanical villain without even providing an explanation for his origin or an explanation as to how he came to the conclusion that organic life was unworthy of accepting the Mantle as well as how he came to see value in Cortana. It’s all really unclear and murky outside random snippets of dialogue. It sort of is implied by the Bastion Forerunner and Exuberant Witness that he was once a living being before becoming an AI.
His role, identity and origin should definitely be elaborated on in Halo 6. Hopefully it won’t disregard it like Halo 5 itself ignored a lot of the plot threads in Halo 4.
My headcanon so far is that the Warden Eternal was once a Warrior-Servant serving the Ur-Didact, but he defected to Faber’s Builder Security after the Didact lost his political battle with him and went in exile. In Builder Security he was put in the position of protecting the Domain and Haruspis on Genesis. But after the Ur-Didact succumbed to the Gravemind’s logic plague, he hunted down the Prometheans/Warrior-Servants that betrayed him, and made them into special classes of mechanical Prometheans. That explains why his design is distinctively Promethean.
The Warden Eternal then managed to flee in his new form before the Ur-Didact was imprisoned on Requiem by the Librarian. The Warden then returned to Genesis, where he aimlessly watched the end of the Ecumene and spent millenia in isolation protecting what was left of the Domain. He ultimately succumbed to rampancy as the centuries went on and began to see ill of organic. Meeting Cortana was the first AI he had met in ages, and he introduced her to his philosophy and accepted her as his new master.
It would be cool if he became natural after halo 5 and decides to work on his own after failing cortana imagine him working with the didact.