Hyperenor was one of the Spartoi (Ancient Greek: Σπαρτοί, "sown men"), the armed warriors who sprang fully grown from the ground after the Phoenician prince Cadmus sowed half the teeth of the slain dragon of Ares at the future site of Thebes. The newly risen men fought one another until only five survived — Echion, Udaeus, Chthonius, Hyperenor, and Pelorus — and these five became Cadmus' comrades in founding the city. From them the noble houses of Thebes claimed descent. (This Theban Hyperenor is distinct from the Trojan warrior of the same name in Homer's Iliad.)
Adapted from Wikipedia, "Dragon's teeth (mythology)" · CC BY-SA 4.0
I.The Sown Men
In Greek myth, dragon's teeth (Greek: ὀδόντες (τοῦ) δράκοντος, odontes tou drakontos) feature prominently in two legends: that of the Phoenician prince Cadmus and that of Jason's quest for the Golden Fleece. In each case a fire-breathing dragon is present, and its teeth, once planted in the ground, grow into fully armed warriors.
The warriors who sprang up from Cadmus' sowing were known as the Spartoi (Ancient Greek: Σπαρτοί), literally the "sown men," a name derived from the verb σπείρω (speírō), "to sow." Hyperenor is counted among them — one of the five who survived the warriors' mutual slaughter and went on to help establish Thebes.
II.Cadmus and the Spartoi
Cadmus, the bringer of literacy and civilization, killed the sacred dragon that guarded the spring of Ares. According to the Bibliotheca, Athena gave Cadmus half of the dragon's teeth and advised him to sow them. When he did, fierce armed men — the Spartoi — sprang up from the furrows.
Fearing them, Cadmus threw a stone among the risen warriors. Each man, thinking the stone had been thrown by one of the others, turned on his fellows, and they fought until only five remained. After founding the city, Cadmus was forced to serve Ares as a slave for eight years to atone for killing the dragon; at the end of his service he was given Harmonia, daughter of Aphrodite and Ares, as his wife.
A variant attributed to Hellanicus holds that only five Spartoi sprang up in the first place, omitting the battle between them; in that version Zeus had to intervene to save Cadmus from the wrath of Ares, who wished to kill him.
III.The Five Survivors
The five Spartoi who survived were Echion (the future father of Pentheus), Udaeus, Chthonius, Hyperenor, and Pelorus. These five helped Cadmus found the city of Thebes, and in ancient times the noble families of Thebes claimed direct descent from them.
Echion later married Agave, a daughter of Cadmus, and their son Pentheus succeeded Cadmus as king. According to one source, all the descendants of the Spartoi bore a dragon-like mark upon their bodies; King Creon used this mark to recognize his grandson Maeon, who had been raised in secret without his knowledge.
IV.Jason and the Colchian Spartoi
The motif of warriors sprung from dragon's teeth recurs in the tale of Jason. King Aeëtes of Colchis challenged Jason to sow dragon's teeth, supplied by Athena, as a condition for obtaining the Golden Fleece.
Medea, daughter of Aeëtes, advised Jason to throw a stone among the warriors that rose from the earth. As at Thebes, the men began fighting and killing one another — but in this case none survived save Jason himself.
V.Legacy
The phrase "to sow dragon's teeth" passed into figurative use, meaning to do something that has the effect of fomenting disputes or strife. Swedish preserves a related idiom, draksådd ("dragon-seed"), for the spreading of corrupting ideas or actions with dire consequences.
John Milton invoked the myth in Areopagitica, comparing books to "fabulous Dragon's teeth; and being sown up and down, may chance to spring up armed men."