If you're the kind of person who wants to propose to your beloved with the phrase "Join me, and together we will rule the universe as husband and wife," then this is the ring for you. Plus, your intended will get to keep all of his or her limbs. (Lava optional.)
If you thought that the TARDIS wedding ring was a little too ... happy and full of diamonds, then this band of cold should be a bit more aesthetically pleasing. Artist Homer Liwag wasn't very forthcoming about his creation, but it's clear that he designed enough dark contours and machine-like surfaces to make a Sith Lord proud.