After he defeated the Assakenians at Aornos, this man defeated King Porus in the same battle  in which he lost his horse Bucephalus. That was after he had already won the battles at  Halicarnassus, Miletus, and Granicus River against the Achaemenids. After his death, Antigon
After he defeated the Assakenians at Aornos, this man defeated King Porus in the same battle  in which he lost his horse Bucephalus. That was after he had already won the battles at  Halicarnassus, Miletus, and Granicus River against the Achaemenids. After his death, Antigonous,  Ptolemy, and Seleucus divided up his empire, which he won with battles against Darius III at  Issus, Tyre, and Gaugamela. Untying the Gordian Knot with a sword and tutored by Aristotle, for  10 points, identify this man who succeeded Philip II as the king of Macedonia.
After he defeated the Assakenians at Aornos, this man defeated King Porus in the same battle  in which he lost his horse Bucephalus.
Alexander the Great or Alexander III of Macedon(ia) [prompt on partial answer]