In one battle, this man left behind the main body of the army while he surprised attacked King Porus by crossing the Hydaspes River with his horse Bucephalus.
The locals called one of his castles the Castle of the White Demon, and in one siege, this man built a kilometer length causeway for his engines to reach an island. He annihilated the Sacred Band of Thebes as the commander of a cavalry wing of his father's army at Chaeronea, and after his death was followed by was the Partition of Babylon and the Wars of the Diadochi. In one battle, this man left behind the main body of the army while he surprised attacked King Porus by crossing the Hydaspes River with his horse Bucephalus. Tutored by Aristotle and famously solved the Gordian Knot, for 10 points, this is what victor at Gaugamela and Issus, the Macedonian king whose conquest ushered the Hellenistic culture.
The locals called one of his castles the Castle of the White Demon, and in one siege, this man built a kilometer length causeway for his engines to reach an island.
{Alexander} the Great or {Alexander III}