Energy.
All Phantoms and people associated with Dead Lands had seen it, most of them in person. Almost the same was true for ordinary people.
Sure, not many ordinary people see energy in life, but through screens, on the news, or by watching some video, it is possible.
Those with deeper knowledge, Operators or military, knew that the energy was inside the Evolution Tree.
True, the Initial Gene was the core, but it was the Evolution Tree that held all of the Phantom's energy.
As the Phantom grew stronger, its Evolution Tree grew, becoming a more complex and massive structure.
Regardless, when it came to K2-Phantoms and below, almost none of them knew what was inside the Evolution Tree.
More precisely... it was similar to the situation with the planet. People knew that inside was a core of molten metals held together by gravity, but no one had ever seen it with their own eyes.
The same thing was happening to the Evolution Tree.
