Ἐφιάλτης

Betrayal is an act of cowardice, associated with damaged self-esteem, shock, self-doubting and anger.

Bearing ugly connotations of deception and dishonesty of a disgusting person who turns against his own, to betray their trust on behalf of an outsider (a foreign government)

Spartans a fierce nation of undefeated warriors, decades after #Persian attempts on invading #Greece, fell due to the betrayal of #Ephilates member of the Greek Malian tribe which chose discretion over valor to collaborate with Persians.

Spartan king #Leonidas occupied and fortified the narrow pass in the Malian lands which would essentially stop Persian invasion, attempt after attempt they could not out-best their Spartan warrior nation adversaries.

Unknown to #Xerxes, with a vastly larger force the “narrow pass” was not the only path around Thermopylae of Malian Lands. Until, after a few days later Xerxes has a visitor that would decide the fate of the Greeks at Thermopylae.

It is the infamous traitor Ephialtes “Ἐφιάλτης” Greek: Nightmare, which he lead the way in exchange for rich rewards across the hills, Pushing Leonidas, a leader with skin in the game, to fight to death with 300 Spartan soldiers, the Thespians & Thebans all to be defeated.

However, this defeat is not the end of the story, #Xerxes could not march through Greece to defeat all city states. The stories of Spartan courage spread across Greece raising the morale of the people and helping other city states prepare.

As for Ephilates he never collected the reward after the Persians were defeated against Salamis and their collapse of Greek invasion. He fled with a bounty on his head, to later die, unfortunately of unrelated reasons.