Wu Zhangkong was already a Hyper Douluo, so it would not be an issue for him to don four-word battle armor. After Wu Zhangkong reached Title Douluo-rank, the speed of his cultivation base had not slowed, but actually sped up instead. As a result, he was able to of break through to Hyper Douluo-rank in a short period of time.
Yali told Tang Wulin that Wu Zhangkong seemed to have been awakened by something during the great explosion. The heart that had been suppressed was freed by hatred. Moreover, the burden that he carried on his shoulders was exceedingly heavy.
Other than the two Limit Douluos in Shrek Academy, only he could be considered a genuine teacher that was still alive.
The rest of the teachers had all sacrificed themselves for the students. They gave him the opportunity to survive at the final moment. What excuse could he give if he let himself drown in sorrow?