“Long dormant, the planet Mercury had sparked back to life. The sun-drenched surface was patrolled by the surging Vex and remnants of the Cabal Red Legion. A simulation world – the Infinite Forest – held secrets and presented a dangerous threat to the galaxy. The legendary Warlock Osiris knew of this threat and attempted to pursue it on his own. His ghost Sagira, alongside Ikora Rey, requested that the Guardians follow Osiris. And by doing so, they were able to destroy Panoptes, The Infinite Mind, the main Vex mind that was leading the assault. In pursuit of an old Vanguard signal coming from inside the Infinite Forest, it was discovered that legendary Titan Saint-XIV was laid to rest by the Vex after a fierce battle. The Vex had seemed to respect the power of Saint-XIV.
Emperor Calus called to the Guardians to enter the underbelly of the Leviathan to find the source of its engine troubles. During this season, Guardians celebrated The Dawning.”