|Theater of operations|
The Amathet are a tol'vir tribe who prided themselves on protecting the works of the titans and wield solar magic. Now, they seek to "become one with the titans" and purge the world of the "corrupted". The Amathet are comprised entirely of stone tol'vir, presumably having slept through the effects of the Curse of Flesh.
The Amathet are not working for the Old Gods. Though they are aware of some corruption within their ranks, they have tasked some to hunt the corrupted down and, in fact, plan to kill N'Zoth by activating Reply-Code Omega and the Forge of Origination, though this would also kill everyone else on the planet. The Amathet see everyone else as no different from N'Zoth and believe they all must be purged.
Very little is known of Sun King Nahkotep who leads the Amathet, but it is known that those closest to him are referred to as "Suntouched", a caste of solar magic practitioners. The Amathet use various idols and monuments to channel their solar magic. The Sun Priests are an ancient order who have walked among all tol'vir tribes, but the ones among the Amathet have twisted the tol'vir's beliefs and weaponized them to justify their crusade.
Sargeras striking Azeroth with his sword unearthed new tombs below Sunstone Terrace, which was their ancient territory, and from those tombs the Amathet emerged. They speak little to other tol'vir, believing them to be betrayers of their sacred duties. They believe that they, stewards of the titans, should alone control the Azerite. When they realized that Rajh and his kin were slain, they constructed their own new watchers, which means they must have an active forge like the Forge of Wills and Forge of Origination. It was later revealed that the Forge they had was, in fact, the Forge of Origination, as they had occupied the Halls of Origination. At the Tombs of the Precursors in Uldum, the Amathet are reassembling broken watchers, which is how they obtain them. Among the Amathet's watchers is Saba-tok who is strangely referred to as a Keeper.
Their bows are apparently different than those of modern tol'vir, giving the Amathet a range advantage.
After N'Zoth escaped the Last Prison and began attempting to recreate the Black Empire, the Amathet began to assault the Halls of Origination and surrounding areas of Uldum, bringing them into conflict with the Ramkahen tribe and their newly formed Uldum Accord. The Amathet now viewed the planet as being too far gone to save, and sought to use the Forge of Origination to end the Old Gods' corruption by purging all life on Azeroth through the use of Reply-Code Omega. Fortunately, this was coincidentally discovered in time by High Explorer Dellorah of the Explorers' League with the adventurer's aid and the Amathet's assault on the Halls was ultimately routed.
Object and items
The Tomb of the Sun King's name presumably refers to Sun King Nahkotep, as he is found here and it is near Sunstone Terrace which was the Amathet's territory before they went to slumber in underground tombs.