Dong Tianyu left some signs of habitation on the Taolang, so that if anyone else came by, they could confirm that Dong Tianyu had been living there through the traces left behind.
After leaving the Taolang, Dong Tianyu activated the Shadow Formation and left the Taolang where it was instead of putting it into the Shadow Space.
Even though the Taolang is a Magic Artifact and any cultivator with a Divine Sense can freely use it once they get it, Dong Tianyu believed that in Pengcheng, and even in the whole nation, he was probably the only cultivator presently, so he felt completely safe leaving it there.
Back in his cave mansion, Dong Tianyu still lived his leisurely life. The generator inside the cave could ensure that electrical appliances worked properly, and his life was not much different from before the disaster when he was home—if he did not leave the cave.