Dusk
In the extremely focused state that he was in, to Z it felt like mere minutes had passed since he began the battle. But the state of the horizon would beg to differ, for even the dusk was coming to a close, with the local star nearly out of sight.
Hours had gone by. After all, even though the mech cut through the Void Dwellers swarm without suffering any harm, it was still a time-consuming endeavor, not to mention that more of them had been falling out of multiple tears as well.
Yet even so, what awaited them was only more grueling than what they had faced. Up on the cliff more enemies awaited them, and they were better prepared as well. Anticipating such a situation was exactly why Z had refrained from using any energy intensive techniques to speed up the process.