Whodunit?

Well, this should be interesting. According to Ocheeva, someone has hired you to infiltrate a party, then kill all of the guests, without any of them witnessing a single murder. Guess someone at Bethesda enjoys playing How To Host A Murder. Or Clue.

Divide and conquer is the name of the game here, as well as blending in - before you enter the house in Skingrad, be sure to take off your armor and weapons, and don some kind of normal clothing. The Deceiver's Finery will be perfect for the job, but otherwise, you can probably steal clothes from any random house in the city.

When you're set up, looking suave and proper, head to Skingrad and find the house. Fafnir will provide you with the key to the house, meaning that you're going to be the only one who can get in or out.

The Killing GameNow that you're inside the house, you'll have to find a way to kill all of the other five guests without being detected. What this basically means is that you have to get them into a room for a little one-on-one time, close the door, then kill them, preferably in one blow. Luckily, there are three rooms on the top floor of the house, each with beds in them. If you periodically check the rooms, then you'll often find one of the houseguests sleeping.

If you're unwilling to go the murderous route, either bribe or Speechcraft your way to get a disposition of at least 70 with each guest. This will unlock additional conversational interactions with each of them, allowing you to manipulate them to your own ends, at least in theory. (If you don't have a lot of cash, feel free to bribe them anyway; everyone's going to die, after all, and you'll get it all back.) You can start with the Dunmer girl, if you wish, who's sweet on one of the other guests. If you can convince her to wait upstairs in his room, you'll be able to follow her up, close the door behind you, and finish her off. Try to get sneak attacks with melee weapons; most of the guests should go down in one hit.

The one guest that's difficult to isolate is the Nord, but if you manage to kill three of the other guests, including the Dark Elf girl, he'll usually choose to fly into a rage and kill them, asking you to back him up. If the last remaining guest is the Redguard, he'll outfit himself in all of his Legion finery and fight back - he may even be suspicious of you, though, so it's best to ensure that he's one of the first guests to go down.

Anyway, when it's down to just you and the Nord, finish him off as quickly as possible. Since there are no more witnesses to worry about, you can kill him in straight combat. Note that all you have to worry about when murdering people is their line of sight; if one guest is in the dining room of the main room, and another one is downstairs, then you should be able to kill either of them without losing your bonus for stealth kills. Just be sure to kill them as quickly as possible, preferably with melee stealth kills.

When you complete the kills and return to Ocheeva, she'll reward you with the Night Mother's Blessing, which gives you a permanent +2 bonus to Blade, Acrobatics, Sneak, Security, and Marksman

hope this helps