I really like this domain for the cleric. It's dark, original, and has to do with the void. The only reasons why I gave it four stars instead of five is because of a few spelling errors in the document itself, not big ones like "on" instead of "one," and that the damage die for some of the spells and the abilities is a bit high. If you changed them a bit it would be perfect. All in all though I would allow this domain in my games. See how my players roleplay a messenger of the void.
[4 of 5 Stars!]