Exodus 4:9

4:9 And if they do not believe even these two signs or listen to you, then take some water from the Nile and pour it out on the dry ground. The water you take out of the Nile will become blood on the dry ground.”

Exodus 32:1

The Sin of the Golden Calf

32:1 When the people saw that Moses delayed in coming down from the mountain, they gathered around Aaron and said to him, “Get up, make us gods that will go before us. As for this fellow Moses, the man who brought us up from the land of Egypt, we do not know what has become of him!”