en.wikipedia.org/wiki/Lord_of_the_Flies

The first half of the sentence is broadly right: "Lord of the Flies" does derive from Baal-zebub / Beelzebub. But the rest of the claim is inaccurate.

Reliable reference works describe Baalzebub as the Philistine god of Ekron and explain the name as "Lord of flies". They also describe Beelzebul/Beelzebub in the New Testament as "the prince of demons" or another name for Satan. None of these standard sources describes Beelzebub as the god of pride and warfare.

In other words, the article conflates Beelzebub with later or nonstandard demonological associations and adds "warfare" without support from the usual biblical/reference tradition. A more accurate formulation would be that the title translates Baal-zebub / Beelzebub (“Lord of the Flies”), a Philistine deity later associated in Christian tradition with a major demon or the prince of demons.