The invisible sonic barrier in the air was like an extremely elastic film in front of Zhang Tie.
This film was not terrifying. Zhang Tie felt that he was completely able to break through it. However, Zhang Tie couldn't break through this sonic barrier even though he had repeated it many times.
The chakras of "King Roc Sutra" were still rotating stably and providing energy for Zhang Tie constantly. Zhang Tie felt that it was still not the highest speed that he could reach. He had not made full use of the flight ability granted by King Roc Sutra. What made Zhang Tie extremely depressed was that he could not break through 750 miles per hour no matter how he struggled although he felt that he could easily break through this sonic barrier. This speed was very terrifying for common knights; however, Zhang Tie was not satisfied with it.
