(SPOILERS) Skyrim Anniversary Edition New Lore
The Anniversary Edition of *Skyrim* was just released and it adds a number of new events with potentially major lore implications to the story of TESV.
In order of descending importance (in my own view, at least, though the first two arguably have implications of equal weight).
This isn't everything, just some of the additions I personally found pretty interesting.
1)***The Cause:*** The Last Dragonborn is called upon to investigate the resurgence of the Mythic Dawn by a cult member that defected, but is too late to prevent the order's assassins from killing him.
Upon investigation they discover that a Master Conjurer named Vonos has reformed the Mythic Dawn (Dagon is largely the instigator, having drawn mortals from across Skyrim to a forgotten Dawn temple to serve as the inner circle by whishpering in their minds, with Vonos being the one most attuned to his will) and is planning to construct a new Oblivion Gate out of Gate pieces left behind from the days of the Oblivion Crisis.
Vonos hasn't managed to bypass the Liminal Barrier (the new barrier is apparently almost impossible to defy, Sigil Stones are said to be so potent that 'a thousand soul gems' would just dissolve in their presence and even they have nowhere near the power to create a working Gate while the barrier is active), but believes a Great Welkynd Stone has the necessary power to do it.
The Dragonborn retrieves the Stone from the chambers of Norion the Undying (presumably an Ayleid Sorcerer-King), goes on to attack the new Dawn in their temple and kills Vonos.
Something goes wrong, however, as Vonos dies, the Gate opens.
Upon reading the cult leader's journal, the truth is revealed: This has all been a deception by Mehrunes Dagon and the death of Vonos was, per their pact, the final piece of a divine ritual 'of the highest order'.
The Gate can only be powered by a Great Welkynd Stone (an artifact of 'untold power' that has been corrupted to become a tool of Oblivion), and the barrier put in place by Martin's sacrifice can only be undone by another of Akatosh's children.
In fact, in a sense, Akatosh himself undoes the barrier as both Alduin and the Last Dragonborn (the emergence of both was predicted in advance by Dagon/Vonos, Alduin is said to have emerged from the Time Wound on the Throat of the World) are clarified to be aspects of the Time God ('soul of Akatosh') clashing with one another (therefore the *'blood of mortals will be on the hands of Akatosh'* and it is this unwitting betrayal that Dagon views as his ultimate revenge.)
The immediate threat of invasion is delayed by the Dovahkiin slaying the Valkyn that were to act as it's generals, eradicating the new Dawn and placing the Red Scar Cavern under the Vigil's control but the damage is done, the barrier remains broken (perhaps not fully sundered, but unraveled enough that occurences like the new Gate can now exist and serve as a staging point for conquest/further interference) and the Gate can not be undone because the only way to interact with it (the Sigil Stone used to create it) has already been destroyed.
Dagon now has a seemingly permanent foothold into the mortal world from which to spread his influence and eventually attempt to take it for himself. Somewhere in Aetherius both Akatosh and Martin facepalm.
All this according to Vonos, of course.
**Ghosts of the Tribunal:** Members of the old Tribunal Temple (clergy, Ordinators, even Hands of Almalexia) locate a stone on which Almalexia once stood from which her power somehow still resonates, they take the stone to Ashfall Tear in Solstheim and build a new temple to the goddess (primarily) and the rest of the Tribunal (the stone itself being carved into a giant statue of the goddess).
The Matriarch of this remnant of the old faith of the ALMSIVI says she can hear still hear Almalexia's voice from the stone and, under her guidance, leads the group into rebuilding faith in the Tribunal and eventually restoring the goddess herself (the tasks given by the goddess include retrieving the lost Masks of the ALMSIVI, drawing the Dunmer back to the Tribunal faith and so on.)
So the Matriarch claims, anyway. Whether those claims are true is not fully confirmed,though, for what it might be worth, the Shrines of Almalexia, Vivec and Sotha Sil found in the temple do administer blessings (if the Matriarch's claims are taken at face value, than the Tribunal might still be around as powerful spirits or perhaps even gods, albeit in a more incorporeal/distant state.)
The Dragonborn can either destroy the fledgling temple or help them spread their message to the extent that they start drawing in new acolytes from across Tamriel.
Whatever is going on with the Tribunal, another forgotten god also appears to still be present in some form.
The Mask of Dagoth Ur was once locked deep within the temple's vault, from within it's resting place, the Mask started whispering to some of the temple priests and enthralled them to the will of Dagoth Ur. One of the priests eventually stole the Mask (allegedly having been shown how to bypass the enclosure by Ur himself) and put it on to become Dagoth's herald.
The Mask gave this rogue priest the power to exhale the Blight and both create and control new Ash Creatures, he now plans to destroy the new Tribunal temple and than go on to spread the Blight across the land once more.
Dovahkiin stops them (the priest issues a challenge, as the Dovahkiin has retrieved all three Tribunal Masks they are seen as a champion of the ALMSIVI that needs to has to die for Dagoth's plans to proceed.)
Incorporeal Living Gods attempting to restore their influence ? Mortal faithful driven to extreme action by remnants of divine power ? Could be either.
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**The Remnant:**
Ever since the Second Treaty of Stros M'Kai and the Aldmeri Dominion being driven from Hammerfell, an elite Redguard intelligence organization, the Remnant/The Eyes That Watch have been keeping an eye on the Thalmor and the Dominion.
Knowing of the threat the Thalmor pose and of their operations in Skyrim, Remnant agents have been operating across Skyrim for over 20 years and, both in Skyrim and in Hammerfell, the two organizations have been engaged in a fierce war in the shadows.
Now, with the aid of a treacherous noble, the Thalmor have abducted a Remnant agent who holds crucial information they could use to conquer Sentinel.
The Last Dragonborn helps rescue the agent, kills the traitor and foils the Thalmor plot.
Also, I have to say, the Remnant are probably the only group of their kind in TESV that actually employs magic as you'd expect an elite organization to (all of their members seen employ invisibility, enchanted armor that enhances stealth and combat ability and fire enchanted scimitars. Their armor/weapons look amazing too, I like them.)
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**Gallows Hall:** The Revenant/Necromancer's Moon (post-apotheosis Mannimarco) is still around and prayers/altars to it can be used to turn Soul Gems into Black Soul Gems.
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Thoughts ? The Remnant stuff appears to hint at a conflict brewing between the Dominion and Hammerfell (already underway in one form), as for the *Cause* and *Ghosts of the Tribunal,* lore implications (say, Alduin and the Last Dragonborn being given a direct spiritual origin as parts of Akatosh) aside, I am surprised they decided to include events that impact the culmination of two older titles so heavily.