The Dark Brotherhood guild can be summarized in three words – Assassins For Hire. They carry out their daily bloodshed int the name of Sithis. They are deadly mercenaries who are dark to the core – To join Dark Brotherhood in Skyrim, you will have to be sinful as they are.
Before joining Dark Brotherhood, you may be attacked by these Assassins – after killing them, loot their bodies, and you will most probably find a note stating ‘The Black Sacrament has been performed’ and that payment has been received for the contract.
You would be doing the same when you join this Guild so prepare yourself for bloodshed.
Join Dark Brotherhood in Skyrim
You will have to act like a Dark Brotherhood member to join this Guild. Head to Windhelm and get into the Arentino house which has a simple lock. Talk to Aventus, he will tell you to kill somebody in Riften’s Honorhall known as Grelod the Kind.
When you get there, enter into the orphanage. Grelod will be talking to some children, just kill her any way you like as it doesn’t need to be clean. You can ask your followers also, once you are done, get back to Aventus.
Keep roaming in the streets of Riverwood until you get a letter from the brotherhood saying “We Know”. After this, you can sleep in a bed for any amount of time to start the next phase of the quest. You’ll be kidnapped by a Dark Brotherhood assassin and wake up in an abandoned shack.
With Friends Like These…
Now, you will have to decide if you want to join or destroy the Dark Brotherhood. If you wish to join, Astrid, the Dark Brotherhood Assassin, will ask you to kill one of the three people in the room; which will start the new quest “With Friends Like These…”.
You are free to kill any one of the three people – even all of them if you desire. Once you kill someone, you will acquire an invitation to the Dark Brotherhood. It’s on the western side of Falkreath.
Once you receive the invitation, go to the main entrance and choose the following answer “Silence My Brother”. Once you’re inside, go and talk to Astrid, she’ll give you some new gear “Shrouded Light Armor”. Now that you have the gear, go to the North where you’ll meet a new family, just on the left side is a word of power.
Destroy the Dark Brotherhood
When choosing who to kill, you also have the option to attack Astrid instead, and take the opportunity to destroy the Dark Brotherhood. This will start the quest “Destroy the Dark Brotherhood”.
Do remember that this is the one and only chance you will ever get to do so; because once you join, you will not be able to kill any of the members of the Brotherhood.