Numbers are not Solterra's weapon, it is morale. Numbers are merely a bonus. What wins war is strategy. Either way, Solterra doesn't fight to win this war, he fights to save his Sister. If he can not reach her, he'd rather die than be treated as a criminal in Cole's eyes. He would rather die than witness his lands taken or watch his Sister be harmed. Neither I nor Solterra are being a fatist, he just doesn't care. He will fight until there's nothing left. It will leave a scar on Pelataria that will never heal.