Area attack, impossible to dodge.
Hou Niao, like a meteorite in a loss of control, was falling, but his speed was far slower than the range of Water Arrows. The only thing he could do was to counterattack with a sword; his Flying Sword struck against the flow, a typical delayed sword move of a Sword Cultivator.
The attacker clearly did not want to drag the battle out for too long. To bully the weaker and still dawdle was just asking for trouble.
Completely disregarding the incoming Flying Sword, instead, after the waterfall of Water Arrows, they added a Water Tornado and were also preparing a third spell, the Heavy Water Skill. The goal was simply to ensure that once the young cultivator was entangled by the Water Arrows, he would not be given any chance at all and would be taken down in one fell swoop.
This was the confidence of a Golden Core Cultivator, both in his attack and in his defense.