Alex used the opportunity of the explosion to teleport behind the woman. If he could get rid of her, he would have an easier time fighting the patriarch.
He broke the array in doing so and his strength wasn't as strong as it had just moments ago. Even then, it was enough for the woman who he attacked as hard as he could.
The woman hadn't realized he was behind her at all. Her focus was still on the explosion in front of her, but the patriarch sensed him.
Immediately, a water aura erupted from him as it covered both him and his sister. At the next moment, Alex felt his strength disappear.
He was feeling a resistance that was softening all the attack that was going out of him. The attack landed on the woman, but it wasn't strong enough to harm her at all.
She immediately turned around and used her fire Dao to try and burn him. Alex teleported at once to avoid that and appeared back in his position for the array.