The moment Kir acknowledged his challenge, Kretos immediately attacked Kir. Kretos didn't use any weapon since Kir wasn't using anything as well and was still in his human form.
'No need to hold back with this one!' Kretos jumped upward and did a somersault kick from above. Kir evaded the strike by sidestepping. Kretos who missed his target hit the ground which shattered upon contact with his leg.
Even though the ground shattered and this move would've unbalanced most opponents, Kir wasn't most opponents. Even with the ground cracking and shaking Kir's stance was steady as a mountain. He then countered with a punch and an explosive mana burst happened which ignited the surrounding air.