Katria, Agmaer and myself rode the lift far down into the depths where we finally found the Aetherium Forge our spirit guide was looking for. She then told me to turn off the steam. Are you nuts? That generally makes things explode! Anyway, after a mandatory fight with its guardians (where I turn the steam back on) I use the rare ore of the key itself to make a crown for Katria. She is happy and finally goes off to Sovngarde (I guess). I run one more rescue mission with Agmaer wherein we slay another master vamp and free a bearded male orc civilian who calls Agmaer "my love". Uhhh, awkward.
With a lot of experience now under his belt I bring Agmaer back to Dawnguard HQ then proceed to meet Serana where she is waiting for me - but not before I instruct one of my people, Bane the khajiit, to tail us covertly from a good distance. I'm not dumb enough to wander around with a bunch of elder scrolls and have no backup, and I figure if anyone can sneak up on a vamp it would be a cat. So into the castle we go via a side entrance. Skeletons and gargoyles seem to be the main guards here, but are generally no match for Serana's magic anyway. A feral vamp and her doggies are the only fangs I get to slay on this excursion.
We finally reach the tower of her mom and find a portal to the Soul Cairn, the only catch being I have to be partially "dead" to enter. Serana offers again to vamp me out or alternatively partially soul trap me which will weaken me somewhat. I obviously choose the soul trap option (because vampires suck!) and then descend into the realm of not quite death, but more like used black soul-trap land? It is a bizzare and somewhat large place, but thankfully it is not as huge nor as darkly foreboding as Blackreach. Oddly the skeleton theme continues here, with bonemen being my primary adversaries. Pity for them my aura whisper removes any surprise attacks they have, since I can pinpoint them, bash them through the sand to make them climb out, and finish off with a sneak attack when they are defenseless.
Lots of non-hostile souls here too, the funniest being "Saint" Jiub, the slayer of Cliffracers! Unfortunately he also has a damned collection quest in here too. Blaaaargh! x_x
Whoa that takes me back.