Willie's transformation looked to be beginning, and from what Felix could sense, it would be a rather flashy transformation.
That meant all of his prey would be alerted by him and two things could happen in this situation:
A. They would all run away from this direction. Making things harder for Felix.
B. They would all run in this direction to devour Willie and gain his ability.
From what could be seen. Willie's evolution to get a fleshly body looked to be rather impressive.
Not visuals alone, the things that went around Willie as he spun his cocoon around him were very interesting to Felix. They were new appliances of energy that he never thought about mostly because his ability evolved his body for him automatically.
If he would have gone through a similar process, he would have learned them by himself, but all he needed to do was absorb the DNA of the target in moderate quantities and wait before his body would evolve by itself.
