Our next stop was to retrieve a holy warhammer for the guy who hears voices in his head at a bandit cave near Whiterun. The first thing I encounter when I get there is an angry face of a guard who attacks me out right (kinda wanted here too). He's soon joined by another, and then by a pair of bandits. Then out of the blue, a familiar cat figure appears - Bane who had been tailing us decided to come out of the shadows to assist. "Khajiit guards your back," he says smugly. With now three of us, there was little danger as we raided the cave and then a second location for more schematics before returning to Dawnguard HQ.
Alas, it turns out the moth priest had been blinded by his own folly and now I have to go do a ritual to read them. The place was easy enough to find, a well hidden and very pretty glade. After attracting some bugs to me (yuck) I managed to read all three elder scrolls in succession (I think purely to make use of the open scroll animation) and got a vision of a map before snapping out of it. At least I'm not blind!
Alternative Solution: Elder Braile Scrolls.
Seems our next task is to retrieve some bow of a god, which is also what Lord Harkon wants apparently. Just as we were on our way out a large mob of vampires and a pair of gargoyles show up! How did they know we were here? We are forced back by the overwhelming numbers and I lose track of both Bane and Serana. I opt to take the high ground on the opposite bank and setup a firing position from there. The exploding bolts and fast reloading crossbow sure come in handy here. One of the thralls actually makes it up to my position but I just shout him off the cliff to certain death.
Eventually I spot Bane far below fighting like a wild cat, even though he is knocked down again and again. It's still enough to keep the enemies in the open though and eventually I snipe the last one with a slow motion headshot. With the last enemy defeated I regrouped with both Bane who had survived the ordeal, and Serana who seemed to be badly wounded (crawling). Got her to feed on an enemy thrall (possibly the one that went sky diving) and upon leaving she was back to her usual self.