The Chronicon ( new lore book ) is probably my favorite to date. Pretty much the first part of the book deals with Calus’ past, most of which was already known.
In section called DCCII, Calus is stewing while thinking about his dead Shadows ( who had all died to Ghaul ), when he is told that Ghaul was killed by a Guardian. Calus immediately makes plans to meet the guardians, he also makes robotic clones of himself, which we saw in the original Leviathan raid.
A later section, DCCCVII, Calus is shown future events by the tetrahedron ships. Apparently, The Guardian ( us ) becomes the Shadow of Shadows, and Calus hosts a huge banquet for the event.
Section MCXII is where it gets really interesting, but also improbable. The Guardian is asked to gather an Army of Shadows, and first we go to Mithrax, who accepts our offer. With him we kill a bunch of Fallen. We then go to Mara Sov, who does not accept, thus, we kill her. We then go to Petra, who accepts, and with her we slaughter the Awoken. Note: Mithrax is later killed in battle outside the Inner Sanctum.
Section MCXX is probably my favorite. The Vanguard and Rasputin are threatened by Calus and his growing number of Shadows, they ask him to remove his presence from the planets and moons his forces are on. The Guardian is sent to meet with the Vanguard to discuss peace, they deny and choose war with Calus. The Guardian, angered by this, responds interestingly: “Who do you think I am? Without me, you have only a dwindling army of ambivalent soldiers. I am the Young Wolf. I killed the Taken King. I defeated Ghaul, roused the Traveller, I silenced the Moon. I stopped the invasion. I broke the curse, I broke the Houses, I killed the Queen! I am the Shadow of Earth!”
Quite a few interesting things with this statement from our guardian. First, we actually said something, that’s pretty cool. Second, it says we broke the curse, so in the future we do finally break the Dreaming City curse. Also, if this in order of events, then the “invasion” hasn’t happened, and we haven’t silenced the Moon yet, this might be alluding to the next year in Destiny 2, where we apparently go back to the Moon. Just some of my thoughts on this dialogue.
The Guardian then invades the Hellas Basin and attacks Rasputin. The Vanguard begs for mercy, but we deny them.
Later in the book, Savathûn enters the scene. A rift opens in the Leviathan and she and her horde of Hive crawl out. But what’s really interesting is a quote from Calus: “But the great emperor Calus had seen Death at the edge of the universe and was not afraid, for this witch and her spawn were not Death.”
This completely silences the discussion of who’s in the tetrahedron ships. It’s the Darkness, not Savathûn. What comes next is really boring because basically we singlehandedly kill her and her spawn.
The book ends with MCVLIII, which is an affectionate letter from Calus to The Guardian about how much he cherished his time with us.
Just thought I’d kind of summarize the book, it’s very interesting and there’s so many fun details throughout.