I am sword bearer. We did it on normal with me as a warlock with fusion grenade with burn and he shot Crota with first half of a clip of his primary and two HoC rockets to get Crota down. I am sure we could get it without Ghorn, but my buddy is already burnt out of Destiny because he has been playing since release and still doesn't have one and is tired of the repetitiveness and crappy RNG drops. It has really worn him down, so he isn't really down to put a lot of practice in killing Crota on hard. :/