Of course, Zhang Xiaoman is not completely unable to use energy transformation right now; he can only use half energy transformation, which is the precondition state required to activate Dark Speed.
This state is not as pure as an energy body, much like the larvae of the Blood Butterfly's Parasitic Spirit, there's no way to be completely immune to physical attacks, so it will still be affected to some extent.
However, a pure energy body is like a Wandering Spirit, capable of completely avoiding physical damage, which is why the civilization races in the Second Universe can never reach the level of High Order Civilization if they cannot master Dark Spiritual Power, as even a half-energy state can essentially eliminate most of their damage.
If they encounter a Divine entity capable of complete energy transformation, they would have no chance of countering at all.
Imagine when you can't hit them, but they can hit you, escaping is almost your only option.
