Online:Of Brands and Bones

Quick Walkthrough
# Talk to the Drake of Blades at the Alliance Rally Point in the Memorial District.
# Find a   and a key to the chapel.
# Go to the Defiled Chapel of Arkay and brand a skeleton.
# Talk to the Drake of Blades in the Undertaker's Office.
# Collect kindlepitch from the Xivkyn Soulbranders.
# Destroy the dig site in the Crematorium.
# Report to the Drake of Blades in the Alliance Base.

Detailed Walkthrough
You'll find the Drake of Blades at your Alliance Rally Point in the Memorial District. The Worm Cult has been digging up graves in the district, looking for corpses to raise. The Drake is particularly interested in a group of branded skeletons, which, instead of being outfitted as soldiers, have been made to dig in seemingly random locations. She'd like to know what they're digging for and why their masters want it. She informs you that skeletons can be branded by necromancers to bind them to a specific task. If you can steal a Daedric brand and a chapel key from the cultists in the area, you'll be able to get one of these skeletons to tell you what their orders are. The Drake wants you to steal a Daedric brand and use it on a skeleton in the chapel. The Drake has already ensured that the cultists won't bother you inside that building.

thumb|right|The Drake's been busy while you've been out bothering disturbed bones
You can acquire a Daedric Brand and the   by killing Worm Cultists and looting their corpses. Once you have both items, make your way to the Defiled Chapel of Arkay. To reach the chapel, head to the western side of the central roundabout surrounding the graves in the center of the district. Walk down the western road; the chapel is in the building on the south side of the road. Brand a skeleton lying in the pile of bones in front of the altar (beneath the three nooses). It will rise, salute you, repeat its orders and crumble. It says something about finding a Dragonfire Cathedral and "snuffing out the light".

Once you've gotten the information you need, exit the chapel and head towards the Undertaker's Office to meet with the Drake. The Undertaker's Office can be reached by heading east or west, then turning north, and making a turn (left if you went east and right if you went west) to go to the center of the northernmost street. The office is west of the Memorial Armory; right next door to it. You'll find her at the tail-end of an interrogation. She attempts to wrench more information about a map out of a cultist before realizing her captive is now dead. Tell her what you've learned.
:''"Dragonfire Cathedral? Are you sure you heard that correctly? Skeletons aren't all that articulate."
:A ghostly voice said to seek the Dragonfire Cathedral and "quench the light."
:"Hm. That must have been disconcerting."
:What do you know about the Dragonfire Cathedral?
:"It's a legend. Folktale … like Arkay's magic breeches. According to the story, Alessia received a vision from Akatosh in one of the old Ayleid shrines beneath the city. Her followers tore it down and built a cathedral there."
:Why would Molag Bal want to find it?
:"The cathedral is supposed to be the resting place of Akatosh's "second gift" to Alessia&mdash;a powerful relic. What the relic actually does? I have no idea. Molag Bal must be after this relic&mdash;that's why he's looking for the cathedral."
:So how do we stop him?
:"The map I took from this idiot points to the crematorium. I'll bet that's where Molag Bal's skeletons are digging now. Honestly, I'm not convinced that the Dragonfire Cathedral is real. But we can't take the risk. We have to stop them."
:So we go to the crematorium and ….
:"We demolish the dig site. Worm Cultists have been using concentrated kindlepitch to clear rubble. The Xivkyn Soulbranders have been distributing it since they arrived. If you can acquire some, we can use it to destroy their operation."''

The cultists are digging intently near the Crematorium. The Drake doesn't think the Dragonfire Cathedral is real, but if it is, you need to destroy the cultists' dig site. She suggests you find   off the corpses of Xivkyn Soulbranders, and use it to demolish the dig site. You'll find Xivkyn Soulbranders along the street in front of and to the west of the Undertaker's Office. Exit the building and collect three samples of Concentrated Kindlepitch. Once you have it, head for the eastern road. Head down the central roundabout, get on the main road heading east, and you'll find the Crematorium in a building on the south side of the street.

Enter the Crematorium. The Drake has disposed of the Worm Cultists within; you just need to set the kindlepitch in front of the newly dug mineshaft. The crate of explosives detonates, completely destroying the dig site. Meet the Drake back in your Alliance base to be rewarded for your part in crippling the cult's excavation.

Notes
You may not be able to enter the Undertaker's Office if you're in a group 

Quest Stages