This build takes advantage of the resist that Leoric gets when he wraiths with hardened-bones as well as the incredible slow from Paralysing-rage. I've been using this same build now for quite a few games with a lot of success. There are so many cool strats involving wraithing and absorbing dmg while you just wraith in place.

Wraith Walk has been highly under rated, but it is really a fantastic talent when coupled with hardened-bones. People don't want to continue focussing leoric when he is wraith walking, especially if he does it at high health, I mean, what's the point right? He will just be gone, so with knowing this, you can take advantage of wraith walking to reduce dmg on yourself, but get right into the action. It's also great for using right before March of the Black King.