So, after going online and failing about 5 times with five different lobbies of people against Grendal (and was about to rage too - was taking screenshots showing me way far away as he's doing his sweating attack and ALL of my other teammates being hit by it), I said screw it - I'll do this solo.
So I did.
And it reminded me of Monster Hunter very much so. Down to my last life. All out of healing potions. As a hammersmith, I don't have the best DS mode, especially if I can never stagger or stun Grendal. So for about 5+ minutes, I was rushing it, getting a swing in, and dashing out, with a tiny sliver of life, no more lives left and no healing items.
Finally, I beat him!
Gave me that nice rush that MonHun always tends to. Very cool!
Then I proceeded to beat the hell out of Skoll. Woo!