Cheng Ji Yu went all out. He wanted to cut out a path of blood and return later to claim his vengeance.
Theoretically, even if there were three of him, he would still be no match for either Zhu He Xin and Zhang Wei Shan, what more now that the two were working together? However, if a martial artist of Gushing Spring Tier threw all caution away and went all out, it was still a very scary thing. Not even Zhu He Xin or Zhang Wei Shan dared to jump into a head-on clash with Cheng Ji Yu. They did not want to be dragged down together with the latter after all.
Furthermore, how long could he last after throwing aside all caution? They only needed to stall him for a while, and after his burst of energy was exhausted, Cheng Ji Yu's battle prowess would naturally take a drastic drop, and by that time, it'd be extremely easy to defeat him.