Interestingly, it is said that. In times of famine, such as when the crops had been struck down by a blight, for example ergot. The Egyptians had a custom that only the first born, both humans and livestock, would be fed, the others had to shift for themselves. Therefore, if the fungal blight was ergot, which is highly toxic to mammals including humans, the first born would be poisoned.

So the biblical story may just be an case of god, taking credit, as he generally did then, for what was done by a fungus.

Yahweh always had a reputation as a petty mountain god who was jealous and vengeful - typical over the top asshole behavior.

The angel of death cast a pox upon their house. That sounds like a benevolent deity? If God was so powerful, why couldn't he get inside Pharoah's head? How could 19th century Christians, if they believe the book of Exodus, justify owning slaves? Rhetorical questions.