ESO Gates of Oblivion/Blackwood Chapter new lore and content plans.
The reveal event for this year's ESO storyline is out, here's a summary of the lore elements and content plans mentioned:
1)The storyline will revolve around an attempted conquest of Nirn by Mehrunes Dagon (who is revealed to have been at this since the First Era), it will be year long (similar to previous year long storylines).
2)The first release will focus on Blackwood with occasional trips to the Deadlands, the final DLC will seemingly take place in Oblivion/The Deadlands themselves (an Oblivion realm as the main playable area, seemingly akin to Shivering Isles). The Deadlands will be familiar, but also different in some ways due to this taking place in the past.
We'll seemingly get to see more of the elements of Daedric hierarchy, bits of it in earlier content and more fully in the final DLC.
3) The story is described as revolving around deceit and a deal with the devil, the Longhouse Emperors once made a covenant with Dagon to gain the power to rule Tamriel in perpetuity.
As his end of the bargain, the Prince created four immensely powerful weapons of mass destruction known as The Four Ambitions (to be granted to the Longhouse Emperors, ensuring their unchallenged rule), now the deal has gone wrong and the four artifacts of Dagon are a threat to all of Nirn. The Four Ambitions are possibly what's symbolized by the four Daedric coins sent after the initial reveal.
4) The storyline will focus heavily on the character of Mehrunes Dagon himself, how he believes Nirn to rightfully belong to him (and possibly other elements of his backstory hinted at in the Commentaries, it might just be the phrasing but the Mysterium Xarxes are said to make one write down/understand the specific alleged backstory), the elements of his sphere that include revolution and anarchy, (both how that informs his own goals and why it draws worshipers to him), what it means for him to be the Prince of things like hope and ambition and how those things intersect, what he considers valuable and what his goals actually are.
5) It's stated that the Daedric Princes are indeed bound to their natures (Dagon himself is said to essentially be the embodiment of 'flipping the table' or 'kicking down a sandcastle to see what the ocean makes of it') but, while those natures are largely static, their own understanding of their goals and how they plan to advance them evolves.
It's stated that the Dagon we'll meet is, in some ways, less experienced than the one from the Third and Fourth Era, he still hasn't quite mastered the scheming and mechanics of big power moves like this and it will come across in the content.
6) We'll visit Leyawiin, the city is ruled by the Council of Legates and defended by the Ivory Brigade, both determined not to let it fall prey to attack again (as it has many times in recent history. We'll also visit Gideon.
7)other major factions include the Blackfin Legion, an Argonian legion loyal to Keshu the Black Fin and a tribe of Argonians who are devoted to Mehrunes Dagon, worshiping him as they believe him to be the real Egg-Child of Sithis.
8) Major areas include the Niben Forest, the Blackwood Bog and Rockgrove. The first two will seemingly heavily emphasize the swampland elements from the region's descriptions, also adding new creatures to the area like giant man eating frogs and Haj Mota.
The last region, Rockgrove, is under the control of the Dagon worshiping Argonians, and will feature a unique melding of Daedric and Argonian elements and architecture.
9) We'll see more of Argonian and Imperial culture, including how the two affect each other (due to the proximity to the Black Marsh border). Some Khajiiti lore too.
10) A mechanic to allow the players to freely choose their starting storyline will be included, potential lore implications as it features a shattered structure somewhat resembling White-Gold/Ada-mantia and portals/windows that represent each major storyline around it.
11) Lyranth and Eveli-Sharp Arrow will seemingly be major characters.
12)A Companion system will be added (they're unlocked through Blackwood quests and can be permanent companions, once unlocked you can: talk to them, level them up, equip them with gear, set their combat behaviors and abilities)