Just remembered a question I wanted to ask; what are/is Time of Tribulations? Or rather, when does it take place?
Time of Tribulations represents the shift from 1st to 2nd Edition AoS, covered in the Malign Portents campaign and supplement. The Campaign is scrubbed off the internet aside from archives and I'm still not sure if it's canon, but the actual supplement is 100% canon and coveres Nagash's preparations leading up to the Necroquake, which signals the start of 2nd Edition. AoS does these events towards the end of an Edition to welcome the new Edition and what its concept is centered around. 1st was mostly the Realmgate Wars, 2nd was the Necroquake and its aftermath, and 3rd is the Era of the Beast.
Anyways, Time of Tribulations refers to the time period before the Necroquake where the Realms were starting to see disturbances in the force as more and more dark omens began appearing. The Gods began forseeing a future full of mindless thralls slaved under Nagash's will, and none of them liked it. Not Destruction who wanted a good fight, not Order who opposed Nagash, and not Chaos who thought Nagash was boring and unpleasant. So they began sending Malign Portents to their prophetic followers and oracles who would lead armies into war in Shyish, attempting to stop the ritual of the Necroquake at the newly created Nagashizzar.
The story is full of twists and turns and includes a bunch of characters like Vorrus Starstrike, the Changeling, Darkoath Warqueen Marakarr Bloodsky and a kooky high off his nose Fungoid Cave Shaman, and represented in the Soul Wars novel, which I hear is good and covers the incident pretty well.
Anyways, there was a campaign system built off prophecies that was played around with and that is the Time of Tribulations. The Time of Tribulations ends when the Necroquake happens (and it doesn't go according to plan because Skaven), and that signals the "Arcanum Optimar", which is the name for the magical shockwave that forever changes magic in the realms, allows for Realm Magic and Artefacts to become more prominent, and creates Endless Spells. The Arcanum Optimar disrupts the workings of the Stormvaults and that starts the "Soul Wars", where hordes of undead Nighthaunt began raising across the Realms thanks to the Necroquake and Nagash leads them from his Shyish Nadir through his Mortarch of Grief, Lady Olynder. She's a dastardly schemer who killed her husband to take over his kingdom and faked tears at his funeral but hid a smile beneath it. Nagash admired her perserverance and devious nature as she ruled her kingdom in Shyish, so Nagash offered her a position as ruler of Dolorum when he turned her Undead. He got pissed at her during the Age of Chaos when she decided to parley with Chaos, but he also respected her because that's the reason he chose her to represent him. She's devious.
So he made her a Mortarch, which as the thread knows places someone under his total control, and he forces her to feel every ounce of Grief across all the Realms because he knows that she never truly felt it in her life. Nagash has a sadistic sense of humor like that.
Anyways, the Soul Wars occurs when the Nighthaunt begin fighting against the magic Sancrosanct Chamber of the Stormcast, who previously were looking over the Anvil of Apotheosis and overseeing reforging. Now they're in the Realms fighting Malignants (AoS name for ethereal undead) and Daemons using their magic.
This got away from me. But I guess it serves well as a basic overview of a few things. I've skipped some details here and there and went a bit too in depth about Olynder. TBH I like her. She is a genuinely interesting female character that I don't think is some weird mysoginistic punchline like some characters (Emmanuelle von Liebwitz) in Warhammer Fantasy ended up being. She also gets some Ws and has a rivalry with Be'lakor, which is a very interesting dynamic. She's smart and strong and devious and has aspects to her personality beyond pure evil. She's a self obsessed tyrant and likely narcisstic and self absorbed, which is why she has never felt grief before Nagash forced her. She only cares about other people as an extension of her control over them, which she loves.