Possible Clues:

• Greek dramatist
• Greek dramatist c525-c456BC
• Has clues possibly about play's ending - as supplied by dramatist
• Greek tragedian
• His hero was bound to be released by Shelley
• Marathon participant outlasted many in dramatic competition
• Playwright of exceptionally classy hue
• Dramatist creating hussy done up with lace
• Greek tragedian (Oresteia)
• Ancient Greek dramatist (Oresteia trilogy)