Breakthrough To Transcendence.

He is the most precious cargo because Legion's entire plan revolves around him. Helios sat down wordlessly in front of the tree and began meditating for his breakthrough to transcendence. 

The plant spirit lit up with green flames as the tree father descended into it. It extended a branch into Helios's back and into the stigmata on it. The branch entered the Stigmata as if there is a hidden dimension within the Stigmata. The green flames spread from the branch onto Helios's body. 

The flame is not an ordinary flame. It is created from the burning of faith which a god does. So the flame is the tree father's god fire. Unlike a normal god fire, it is full of divine power, divine will, and divine life energy. It is more of the spark of life.