I’ve been off work recently post-sinus surgery, so I’ve been re-reading EoR and thinking more about converting it into an Eberron-only campaign.
Firstly, Vol will replace Vecna. Her personal goal of reactivating her dragonmark and ascending to become a god of death works perfectly here.
I’ll replace the Vecna cultists with Emerald Claw agents.
I think I’ll drop the “Power of Secrets” mechanic and just make it so people are being kidnapped and sacrificed to power the ritual. No secrets necessary.
For the Wizards Three, I will most likely replace Alustriel with a Chamber dragon in disguise (e.g. Narcy of Xandrar from the Oracle of War series).
I can either replace Tasha with Sora Katra or have Tasha be the adopted human daughter of Sora Kell and just adapt her to Eberron that way. Another option might be to replace Tasha with a member of Aerenal’s Undying Court.
For Mordenkainen/Kas, I will use Mordakhesh instead, but I’m not sure if I’ll have him be open about his identity or keep the surprise twist. If I keep it, I’ll have him masquerading as Merrix d’Cannith or someone like that.
I’ll replace Miska the Wolf-Spider with Rak Tulkhesh. The Eberron book says Rak Tulkhesh is bound in a group of scattered dragonshards. How perfect is that? The Rod of Seven Parts can be made of dragonshards, and it was broken and scattered to keep Rak Tulkhesh imprisoned.
Reassembling the rod will enable Mordakhesh to free his master. I can make it so the rod is also needed to stop Vol, so it’s an opportunistic timing thing on Mordakhesh’s part. Perhaps he can even try to persuade the PCs that releasing Rak Tulkhesh will help them to defeat Vol.
So Alustriel’s sanctum can just be a fancy mansion in Skyway above Sharn.
I might have Sharn’s council ask the PCs to look into the kidnappings of the nobles. Instead of Evernight, the PCs can end up in the Mabaran version of the Amaranthine City.
Web’s Edge can be in Khyber somewhere, and I can replace Lolth with Sul Khatesh.
The wreck of the Lambent Zenith and the corpse of the dead god is trickier. I don’t want any Spelljammer or dead gods in my Eberron. This bit might have to take place in Xoriat (or in a Xoriat manifest zone) and maybe it’s a seafaring ship rather than a spacefaring one. Maybe the ship’s captain is a radiant idol.
The Mournland section can stay as it is.
The Death House section can be somewhere in Karrnath, and I can replace Strahd with Kaius.
The Dragonlance section can either be in the Eldeen Reaches or in Lamannia. Maybe Lord Soth could be a corrupted Pure Flame zealot or something.
I’m not sure what to do with the Nine Hells casino, but maybe that could be in a demiplane in Khyber? Tiamat is the Daughter of Khyber, so she can stay, I guess.
The part of Pandemomium where Miska is can be replaced with Rak Tulkhesh’s heart domain in Khyber. The part where Vecna is can be beneath Vol’s fortress on Farlnen.
That’s about as far as I’ve got so far.