The ground and clear streams were dyed a lurid red by the fresh blood from the genetic lifeforms that lay all around Zhang Lie.

Invisible energy filled the air, floating out of sight—spiritual essence. 

All lifeforms had souls. Upon their death, spiritual essence would dissipate into their environment. Under ordinary circumstances, such spiritual essence would disappear rapidly. However, the mud in this valley was very special, and it could bind the spiritual essence and prevent it from dissipating.

Zhang Lie killed lifeforms in the valley for three whole days, finding quite a large number of superior-grade lifeforms, but never the special...