Dreams signify the subconscious thoughts that are buried deep within one's hearts. That is at least for the cultivators of the realm.
The screams of dying enemies, the torturous events one has seen unfold, that time when they are humiliated. There are many things a cultivator can dream about.
It was, after the reflection of their true experience or deep seethed fear.
Inside Wang Ling's dreams, there would always be a crimson moon and the skies would always seem as if it was bleeding. Corpses would lay on the ground, mutilated and mangled.
Entrails were all over the place and a mountain peak was dyed red as from afar. In the middle of this mess was a young man who stares at the skies, tears of blood streaks down from his face as a headless corpse knelt down before him.
On the background of it, all was a burning temple. The corpses of children who had widened eyes. Fright was still present even in their death.
thanks for reading, Merry Christmas XD