Hi Bungie Lament is not working in the nightfall as an anti barrier weapon. The champions are fully regenerating whilst being hit with a sword. You waste over half of your ammo on one (58 ammo so 29) . No I have not made a video but I am sure I will not be the last person to say about this. Respectfully all the best.
P.S. Yes I am revved up when attacking a champion I understand that is when the sword is antibarrier but it is not working hence my post.