I can't decide between killing Astrid and destroying the Dark Brotherhood, or joining them. Let me give you a bit of info about my Character. He is a pure mage who used to be a priest of Akatosh back in Cyrodiil. Before that he was born in a Forsworn tribe deep in the mountains West of Markarth. His main goal is domination of all who will not bow to his power, and eventually I will make him into a vampire.

I had a similar character a while back. He was once an honourable and Noble Breton wizard, but upon growing in strength and power he also grew in arrogance, eventually dabbling in Necromancy.

Anyway, on the matter of your question. Well, your guy, in the cabin, has complete control over the three captive's lives, so that, and since he seems to be growing darker, he should join the Dark Brotherhood.

Join the DB. The DB/vampire combo works well together.

Alright, thanks guys and thanks to Tommy for sharing the story of one of his characters.

You may also find that you get to have some fun with the DB after some missions.