Instruments of Death - Item References and Flavor Text in Patch 9.2 Sepulcher of the First Ones

wowhead.com:

Following our review of unique items in Patch 9.2, we're taking a look at some of the item references and flavor text in the upcoming Sepulcher of the First Ones raid, to help unravel the story of Eternity's End and speculate on where our fateful showdown with the Jailer might lead.

Naturally, several items in the raid directly refer to the Jailer, Zovaal. It's no secret that the original arbiter of death has grand designs on Azeroth, which are well represented in the flavor text, although it's never been clear as to exactly why Azeroth has been ordained for destruction. We previously learned that Frostmourne, the Helm of Domination, and by extension the Lich King were created in order to extend the Jailer's reach to Azeroth — seeking some hidden secret of the First Ones. We can now presume that secret is Azeroth itself — the nascent world soul growing within the heart of the world, believed to be more powerful than Sargeras and a threat to even the Void Lords… though seemingly also key to the Jailer's plan to unravel the designs of the First Ones. Beyond the Jailer, there are several other character references both new and old. The Ruined Crest of Lordaeron most likely refers to Arthas, so there's not really any new information there, and we previously discussed the Priest and Death Knight class rings obtained from Anduin, though Rygelon's Heraldric Ring presents an interesting question. We know that Rygelon is a Constellar, who like Algalon the Observer before him, is something of a celestial watcher. But while Algalon was specifically commissioned by Aman'Thul to watch Azeroth for signs of Old God corruption, Rygelon's allegiances are not defined — the dungeon journal tells us