Firuan tells his magicians what to do and they're not worried or scared at all. They throw pieces of rope on the ground and they began to wiggle like snakes. But when Prophet Musa throws down his own staff and it turns into a serpent it eats all the pieces of rope. The magicians suddenly realize that prophet Musa is the real deal and bow down in prostration saying they believed in the faith of  Musa.

The Magicians

Firaun was furious and demanded if they didn't take back their words they'd be punished. They didn't change their minds and Firuan cut off their hands and feet and then killed them. Allah told Prophet Musa to warn Firuan if he and his people continued in their ways they'd be punished. He was too proud to listen.