At Sangrod Front, Grace and the others also fought Belphegor for almost two days. Like Asmodeus, Belphegor didn't have as high an HP bar as Leviathan. Unlike Asmodeus, he could not cast recovery spells. What he had was his clones, which healed him a great deal of HP when he consumed them.
He just consumed another clone. He had only one clone left. Even so, he was not nervous.
While he fought the four outworlders, his army continued battling the defenders. The defenders spared many troops to form a wall to block his demons from coming to his aid. A useless move, in his opinion. None of his demons would come to his aid unless he called them over. He never thought of the need to call them over, even when these outworlders forced him to consume his clones to the last one.