As Dean shouted so, he strongly parried Perseus' Harpe to the side, taking a step forward and slashing his body. Unfortunately, his defensive power as an Ascendant was way too high for Dean. His sword didn't leave a scratch on him. However, he was not going to give up in the first attack!
'If it didn't hurt him in the first, attack again!'
A second attack came, faster and stronger, hitting him squarely on the chest, but just making Perseus slide across the snow by a few centimeters.
He even tried to pull back his sword to defend the next one, but once Excalibur collided against Harpe, it got brushed off of the way to open space for another attack.
'Again!' Dean thought, prompting himself to continue pushing even further. 'Claire is right behind you now, so you need to keep going!'
Another slash came, followed by a loud thud as the blade was only able to push Perseus' body forward.