Diades of Pella
Diades of Pella (Ancient Greek: Διάδης Πελλαίος, romanized: Diádēs Pellaíos), surnamed the "Besieger" (Πολιορκητής, Poliorkētḗs), was a Thessalian inventor of many siege engines, student of Philip II's military engineer Polyidus of Thessaly. He lived in the 4th century BC. Diades accompanied Alexander the Great in his campaigns to the East.