The undead army awakened by Su Ausis, all belong to undead creatures or constructs, are completely unafraid, and at the same time lack intellect, so they don't go mad under the influence of the Soul Summoning Mantra.
Otherwise Leon believes that a fierce god matched with the Soul Summoning Mantra could solve most enemies, leaving only a little bit of enemies to deal with easily.
With the fierce god and Soul Summoning Mantra being ineffective, Leon had no choice but to initiate the Three Heads and Six Arms Dharma Body to slaughter, dealing with those undead troops was like cutting through grass, but Su Ausis was really somewhat troublesome.
Leon felt that apart from transformation school spells, Su Ausis had used spells from all kinds of schools, even Priest spells like the Spiritual Body Weapon.