IMO, dark one’s set is the catalyst to ALL builds in GD because:
- How accessible it is
- How great its performance is
With it you can farm end game content, and since gear drop is more or less randomized, you’ll be able to build up a large library of items quickly.
So yes. You can. But I you might have to level a second character (sentinel for more CDR for more BH spam, or cabalist for better flat damage and stats).
Ideally, I wouldn’t use BK set on a ritualist.
“Need” is a strong word. You don’t need BK set to use bone harvest effectively, though it will not be perform effectively in end game challenges.
This is a noob trap. Not enough RR (resist reduction).