After a few days, many creatures and spirits had come to harass the shelter. There hadn't yet been any elites, though.
Still, with Ancient Sky Mirror there, Han Sen didn't lose much. The place did not have the power of Moon Spring, but Ancient Sky Mirror had many super elites inside it. When the mirror started to lose energy, Han Sen could refine the souls inside for nourishment. As a result, there was no need for concern with the mirror's energy.
Of the creatures that were killed, some were eaten and some were absorbed by the mirror. It wasn't much energy, but it was better than nothing.
Han Sen kept on practicing with the Dongxuan Sutra. He needed his Bulwark Umbrella to become super, and when that was done, he could focus on leveling up to reach the Fifth Sanctuary.