Epizelus

Epizelus (alternatively spelled Epizdelos, Epitzelos; Greek: Ἐπίζηλον), the son of Cuphagoras (Greek: Κουφάγoρας) was an Athenian soldier who fought at the Battle of Marathon in 490 BCE.

The only author to mention this individual is Herodotus in his Histories:

Historical value
The description suggests that Epizelus suffered from hysterical blindness (referred to as a conversion disorder).