When the Vajra Skill reached a proficiency of 200/500 in its first level, Chen Yi suddenly felt all the Qi and Blood energy in his body surging toward his skin. Coupled with the hardening effect that had been accumulating over the preceding days, his skin began to change at a speed visible to the naked eye. Its color darkened slightly, and it thickened as if a new layer of cuticle had formed, becoming far tougher than ordinary cowhide.
Chen Yi tested it with a kitchen knife from his home. He lightly drew the blade across his skin, and not even a mark was left. He gradually increased the pressure; it wasn't until he exerted about two hundred jin of force that a white line appeared. He had to apply nearly four or five hundred jin of force before the blade finally broke the skin, and even then, despite the cut being nearly a finger-width deep, there was no blood and almost no pain.
"What an incredible level of defense!"
Chapter 26