Dark Brotherhood (Skyrim)

The Dark Brotherhood is a group of assassins who are willing to assassinate anyone that they are paid to.

Background
The Dark Brotherhood has operated in Tamriel for centuries, having many clandestine sanctuaries across the Empire. They worship Sithis, the serpent god of entropy and chaos, as well as the Night Mother, who is the spiritual leader of the Dark Brotherhood. Their operations in Skyrim are based out of a sanctuary located in the Pine Forests in the hold of Falkreath, west of the city.

Joining/Destroying the Dark Brotherhood
While on your travels in Skyrim, go to any inn and ask for rumors. The innkeeper will tell you that there is a child trying to summon the Dark Brotherhood in Windhelm.

You could alternatively talk to Idesa Sadri inside Candalhearth Hall in Windhelm and ask about a cursed child performing the Black Sacrement. Idesa can also be overheard talking to Grimvar Cruel-Sea about the child, Aventus Aretino, outside the Aretino Residence. Aventus Aretino can be found inside the Aretino Residence, which is has a novice-level lock. The child will offer you the Innocence Lost quest, which will lead to the quest With Friends Like These..., (After Innocence Lost has been completed, a courier will appear and give you a note with the imprint of a black hand and the words "We Know" written beneath it. If you do not receive the note, wait for a couple of days. Once you receive the note, sleep in any bed) ...whereupon you will be offered an invitation to join the Dark Brotherhood or an opportunity to destroy the organization (Destroy the Dark Brotherhood! ).

Contracts
Upon visiting the Brotherhood's secret sanctuary, you will have to speak to one of the "brothers," who will then give you three contacts to complete. These three contracts are of low priority and have no time limit. You may carry them out one by one or you may do all the contracts given to you in a single session and return once all are finished.

Contract 1: Kill Narfi

You must travel to the town of Ivarstead (up the mountain from Helgen) and kill the beggar Narfi.

Contract 2: Kill Ennodius Papius You must travel to Anga's Mill (to the left of Windhelm) and kill the ex millar Ennodius Papius.

Contract 3: Kill Beitild You must travel to Dawnstar at the north of the map and kill the mine boss Beitild.

Mourning Never Comes
-Speak with Astrid

-Talk to Muiri in Markarth.

-Kill Alain Dufont

Whispers in the Dark
-Hide in the Night Mother's coffin

-Eavesdrop on Cicero.

-Talk to Astrid. You are appointed Listener of the Dark Brotherhood, but Astrid sends you to talk to Nozir.

The Silence Has Been Broken
-Speak with Astrid, she tells you to go speak with Amound Motierre

-Amound Motierre wants the Dark Brotherhood to kill several people, all of whom lead to a primary target-the Emperor himself.

-Report back to Astrid with the letter(you can open and read the letter Astrid will comment about that before she sends you to kill Vic) and amulet

-Go to the Ratways in Riften and show Delvin Mallory the amulet

-Report back to Astrid

Bound Until Death
-Go to the wedding of Vittoria Vici

-Kill Vittoria Vici

-Report back to Astrid

Breaching Secruity
-Speak to Gabriella, she gives you a contract to kill Gaius Maro.

-She gives you a bonus contract to kill Gaius Maro, in one of the main cities.

-In order to do so, you must steal Gaius Maro's travel schedule in Dragon Bridge.

-Plant the Incriminationg Letter on Gaius Maro's body.

-Report back to Gabriella

The Cure For Madness
-Talk to Astrid. Cicero is now a traitor, and you must kill him.

-Search Cicero's room to find any leads to where is ran off too.

-Talk to Astrid, she tells you to go after her husband. Astrid also give you her loyal horse Shadowmere. Shadowmere cannot die, but she can be knocked down.

-Locate Arnbjorn

-Talk to Arnbjorn

-Enter the Dawnstar Sanctuary where Cicero is located. The password for the sanctuary is "Innocence, my brother."

-Kill Cicero, or leave the Sanctuary. Cicero begs for mercy and ask you to lie to Astrid that you killed him.

-Report back to Astrid