Enoch's third wave was coming to an end. He would be able to solve this problem in less than 10 minutes.
However, he wasn't in a hurry. Now was the time to gather intelligence, as the others didn't know when the third wave would end.
Enoch was probably the only one that had yet to clear the third wave, so he could control the time.
According to the rules of the invasion, if he didn't kill the last zombie, the time would be extended.
This was also one of the things that Enoch wanted to test.
Enoch had the Berserk Rats stop when there were only two zombies, and then they waited patiently.
He wanted to see how much time he could tolerate.
There were many benefits to doing this.
The biggest benefit was that he could control the time of the invasion and make a series of preparations for the future.
He could also make deals with other Divine Tree Masters during this time.