The trailer begins with Master Chief floating through space, making his way through the wreckage of a ship while talking to the Pilot, his human companion, through a comlink. Master Chief eventually encounters the mysterious AI, whose voice sounds suspiciously like Jen Taylor’s Cortana. When asks her where he can find Cortana, the AI responds that “the rogue AI known as Cortana is gone. She’s been deleted.” The only problem is that neither Chief nor the new AI know how exactly Cortana was deleted. The AI reminds the Spartan that her mission was to “enter this installation, imitate Cortana, and lock her down for retrieval,” while Chief was supposed to transport Cortana back to the USS Infinity for deletion. The AI reveals that she was also supposed to be deleted upon “successful deployment” but that hasn’t happened either. Thus, the game’s central mystery is revealed. Chief decides to take the new AI with him and figure out what happened to his old friend. Previous trailers have mostly dealt with the aftermath of humanity’s war with Cortana’s Forerunner forces. In last year’s gameplay trailer, Chief and the Pilot found themselves on Installation 07 (Zeta Halo) after the Banished destroyed the UNSC fleet, the war already lost. Until now, one could have just assumed that the Banished allied themselves with Cortana, helping her put an end to the UNSC in order to achieve her goal of galactic peace. But with the new teaser suggesting that Cortana has been deleted, it’s clear there are still plenty of missing pieces to this puzzle. In the meantime, what else do we know about Chief’s new AI companion? Her “name,” for starters. According to 343, she’s simply known as “The Weapon.” The studio hopes that the familiarity of the AI character as well as the mystery behind her role in the story and how it connects to Halo 5 will attract both new and veteran players. “We are continuing the story of the Master Chief and Cortana from Halo 5, but also telling a story that’s welcoming for new players,” wrote Halo Infinite head of creative Joseph Staten in a blog post. “Cortana’s fate is one of the Infinite campaign’s big mysteries, and early in the story, you will meet a new UNSC AI, ‘the Weapon,’ that was created to help stop Cortana. Together with the Pilot, the Master Chief, and the Weapon begin an epic adventure to explore Zeta Halo, defeat the Banished forces who control the ring, and unravel even more mysteries along the way.” The Weapon, who we assume will get a better name later (maybe even adopt the name “Cortana”), plays a big role in Chief’s new adventure, then, and fans of the original trilogy of games will likely appreciate having a witty AI companion in their ear again after years without Cortana. More and more, 343 continues to show how it hopes to go “back to basics” with Halo Infinite: a new Halo ring, classic enemies and weapons, and now a new AI to guide you on your missions. Halo Infinite is coming to Xbox Series X/S, Xbox One, and PC this holiday.