Exodus 7:21-22

How were Pharaoh's Magicians able to perform signs and wonders? Well they could only manage for the first three. On the first, their serpents were eaten by that of Moses. On the second and third they made things worse. More blood, more frogs! And no undoing Moses curses.

Hardly a resounding demonstration of their skills, though it served to allow Pharaoh that false-sense of superiority that his men could conjure just as well as Aaron and Moses. By the fourth occurrence though even they conceded defeat admitting that 'this is the finger of God'.

While the magicians recognised God's authority however, Pharaoh wouldn't. For the next three trials he would face ludicrously small foes of gnats, flies, and a pathogen too small to see at all. An interesting episode for sure.