score:4
Perhaps the word 'gods' here can also mean the kings and lords. That would be a question for Hermeneutics.
However, it is widely believed among Egyptologists that the Pharaoh was considered a god-king of sorts and a descendant of Ra, an Egyptian deity. Source 1 Source 2.
I do not know of any other place where these gods are mentioned again in the Bible. The closest, similar event I can think of is Nebuchadnezzar in Daniel 3 creating an image of gold and decreeing that all worship it. Some have argued that it was a statue in Nebuchadnezzar's likeness, although, the Bible says no such thing.
However, after reading a few books on the topic of pagan worship at the time of Christ, emperor worship was somewhat common. Everything from Augustus building up the Imperial Cult, where he was prayed to and "worshiped", however casually, to the Candace of Kush (modern Ethopia) ruling by divine right as the incarnate god. This timeline, though, is about 1500 years after Ramases. Still, the Egyptians had many gods they worshiped, including the Pharaoh, and these verses likely are referring to them.
Upvote:3
While the Egyptians did treat pharaoh as a living human god and his first born their next god. The verses as best I see primarily refers to the false gods ra and the like. Each of the plagues were executed against a particular Egyptian deity. Source wikipedia. Especially the turning of the Nile into blood because many of their gods were connected to the Nile. Source wikipedia
Exo 7:17 Thus saith the LORD, In this thou shalt know that I am the LORD: behold, I will smite with the rod that is in mine hand upon the waters which are in the river, and they shall be turned to blood.
Exo 7:18 And the fish that is in the river shall die, and the river shall stink; and the Egyptians shall lothe to drink of the water of the river.