Sha Peng's courage fled pretty quickly. He would not have blinked if he was faced with eight or even ten opponents. However, there was a big gap between eight and a few dozen.
They were not at the same level of threat. As the saying goes, it was difficult to fight four hands with two fists, let alone dozens or even hundreds of hands. Even an Acquired Stage expert would find it very difficult to deal with opponents at this level. At most, they could barely protect themselves. It was too difficult to defeat so many enemies. And these opponents were wearing armor.
Most importantly, the leader of the opponents was an Acquired Stage expert, which made things even more difficult. There was almost no chance of winning.