Damian had a reason for turning off the effects of all his constitutions.
During the trials, he had subjected his body to extreme conditions by surviving hundreds of intense explosions, absorbing enormous amounts of energy that could have caused him to explode from within, and sitting inside fire essence-filled lava for eleven days straight.
His constitution and talents allowed his body to become incredibly strong by adapting to these extreme conditions.
Even Damian didn't fully understand how strong his physical body had become.
When the Heavenly Sword Demon attacked him, Damian had deactivated all the effects of the four elemental essences, significantly reducing his durability and endurance.
This left his body highly vulnerable, allowing the Heavenly Sword Demon's attacks to work effectively.
Despite pretending to defend himself, Damian wasn't actively resisting.
