your talking about the lizard fight correct? where you fight unkillable lizard skeletons that will only die if you remove every curse field in the entire area... oh.. and they can shoot curse arrows so good luck..
since bless costs a source point now me and my multiplayer team basically had to cheese that fight.. by having our air mage continuously leave the battle to recharge tornado and come back in.. it was the only way to clear all the curse and kill them for good.
I just fill the whole area with oil so a single bless on the enemy will affect all of the necrofire and making the enemies vulnerable. I do this while keeping them downed with KD arrow because when they respawn, they don't have armor.
It does get boring though after you have to repeat the fight multiple times and I just skip the fight by jumping through the gap in the wall -> Teleporter pyramid and walk right into the portal.