Plague: Death of the Firstborn
Source: Nav
Exodus 11:4–7
So Moses declared, “This is what the LORD says: ‘About midnight I will go throughout Egypt, / and every firstborn son in the land of Egypt will die, from the firstborn of Pharaoh who sits on his throne, to the firstborn of the servant girl behind the hand mill, as well as the firstborn of all the cattle. / Then a great cry will go out over all the land of Egypt. Such an outcry has never been heard before and will never be heard again.
Exodus 12:17, 29, 30
So you are to keep the Feast of Unleavened Bread, for on this very day I brought your divisions out of the land of Egypt. You must keep this day as a permanent statute for the generations to come. / Now at midnight the LORD struck down every firstborn male in the land of Egypt, from the firstborn of Pharaoh, who sat on his throne, to the firstborn of the prisoner in the dungeon, as well as all the firstborn among the livestock. / During the night Pharaoh got up—he and all his officials and all the Egyptians—and there was loud wailing in Egypt; for there was no house without someone dead.