Before the many experts, he looked majestic and intimidating at the scene with Heaven Ultimate Gods and Grand Ultimate Gods surrendered under his feet, but he was also on the cusp of what could be a storm as all he had was the supreme life rating pressure. His true strength...was far inferior to anyone on that battlefield.
Any random Heaven Ultimate Gods were enough to crush him.
Therefore, he had to maintain an imposing posture without allowing any room for mistakes. Otherwise, he would not be able to leave the battlefield safely let alone retrieved his Stately Painting once his strength level was exposed.
He had simply done a very good job at disguising himself to the extent that those experts on the battlefield had completely believed him to be an invincible super expert.
The extremely powerful life rating pressure he exerted was of course the crux behind his disguise.