The lack of story in Destiny has me reading the grimoire cards online and through the Destiny app. I have to confess, I find the grimoire cards quite intriguing, and they just keep me asking more questions. Luckily, I am not alone in this search for the story behind Destiny. There are numerous forum posts across multiple sites, with posters attempting to explain their interpretation of the cards, and the "story" of Destiny. Given the subtle hints from the cards, I have written my deduction on how the next DLC raid included in the House of Wolves will play out.
For the first area, I am hoping that it will be a huge open field with limited cover. The goal would be for a guardian to reach two different points to deploy their ghost to disable Fallen communications. As you run through the field, the Fallen will deploy Pikes to harass guardians in hopes that you never reach the necessary console. The Fallen will also constantly bombard you with two walkers from a distance, requiring the remaining guardians to provide covering fire.
The following area would take you inside a skiff bound for the Reef, setting you up for some close-quarters combat. You have to fight your way through swarms of Vandals and Dregs to take control of the ship and enter the Reef undetected.
Deducing from the grimoire cards and the leaked information that the raid is rumored to be in the Reef, I would guess that the main boss for the House of Wolves DLC raid would be Kaliks Prime, which is believed to be the Prime Servitor of the House of Wolves. The Queen has every reason to send you to kill Kaliks Prime, because Aksor, the Archon Priest (which we defeated in a Venus Strike) ravaged numerous Awoken enclaves, and is one of the Kaliks disciples.
For the final area I believe we will be facing Kaliks Prime, but The Archons will defend him. These Priests are what links the Fallen and the Servitors together. Given that the most difficult part of the Sepiks Prime Nightfall was the annoying Captains with arc shields, maybe they'll use two Archons with Arc shields and modified shock rifles. Nothing like seeing six guardians scatter to look for cover when an arc projectile is tracking them.
The House of Wolves expansion pack will be releasing on March 10, 2015.