“A successful assault from a Cabal faction known as the Red Legion crippled the Last City’s defenses and placed a powerful siphoning device onto the Traveler, disconnecting the Light from the Guardians. Many Guardians and civilians were killed in this occupation, and many others were forced to flee in hiding. A noble few who still had a faint connection to the Light were drawn to the European Dead Zone. There, a broken shard of the Traveler provided a connection to the Light, empowering the Chosen few with upgraded powers. While Humanity began to regain territory, the Red Legion utilized their superweapon known as The Almighty and focused this weapon on our Sun. Guardians eventually infiltrated the Almighty and disabled it, although a good portion of Mercury was destroyed. Civilians and Guardians, both lightless and light empowered, led a covert strike against the Cabal occupied city in an effort to retake their city which eventually came down to a showdown against Ghaul, the leader of the Red Legion.
When Ghaul absorbed the power of the Light, the Traveler freed itself from the constraints and destroyed Ghaul. In a pulse of light that stretched throughout the solar system and beyond, the Light was restored to the Guardians. This beacon however triggered a response from the dormant Pyramid Fleet that was waiting somewhere out in the galaxy. The Dark Fleet started its journey to our Solar System.
The now exiled Emperor Calus called to the Guardians when his great Leviathan ship parked near Nessus. A group of Guardians was challenged to defeat him, or rather his robotic self. During this season, Guardians celebrated the Festival of the Lost and focused on strengthening their arsenal after they lost their Vaults during the Last City assault. Guardians also complained about the city’s decision to retool their personal inventories and the performance of their weapons.”