Although the physical movement was simple, the energy movement was more complex than a nightmare, and more powerful than anything ever produced by a King in the history of the known universe.
As an Ancestral Grade item, it was imbued with a powerful skill which would grant the wearer access to the Spell Framework of an Emperor level skill. The energy powering that framework would be the wearer's energy, of course, and thus the power that the skill could manifest would depend also on the wearer.
A King level warrior would be able to unleash one of the most powerful King level spells in existence, while an Emperor level warrior would merely unleash a slightly more powerful than usual Emperor level spell.
With Wu Kong's Darklight Energy, he transformed the slightly stronger than usual Emperor level spell into a monstrosity that would strike fear even in Hegemons.