Isaac actually knew the moment Liu Li finished off the High-level Earth Elemental Spirit, but he didn't turn back right away. Instead, he kept his attention focused on collecting data on the Flesh Mutation.
For one thing, the data was truly important. For another, if he turned around the second the fight ended, wouldn't that just prove he knew Liu Li's identity?
'If I'm going to put on an act, I should at least make it plausible.'
Sure enough, after changing back, Liu Li glanced in Isaac's direction. Seeing him still immersed in his magical research, she breathed a small sigh of relief before throwing herself back into the fray to clean up the battlefield.
Although Liu Li's true form possessed a special, powerful dissolving ability originating from a Demon God, she rarely used it because its appearance was simply too grotesque. Even when Isaac wasn't around, she wouldn't use it unless it was an absolute last resort.
