William's body had been thoroughly controlled by the Order Element, suppressed by its abilities despite only being E-Rank.
Most of the fault could be placed on William himself, since his Soul Strength was just too weak compared to his other abilities. A Golden Core Cultivator's E-Rank Magic would have the combat power of the early to middle stages of the Golden Core Realm, while William's own Soul Strength was only somewhere between the Golden Core and Nascent Soul Realm.
There was only a small bridge to gap for the Order Element, but it was a Mythic-Ranked Element, so how could it be as weak as one of the Basic Elements? It wasn't!
William could tell firsthand that the E-Rank Order Element was very slightly stronger than his own Soul Strength, but it was enough for the Chaos upgrade to gain the upper hand. He used all of his will to resist the Order Element's possession, slowing down every movement to a crawl.