Mago fought with Hannibal in the early Italian campaigns, and played a key role in major battles. Soon afterwards, along with Hamilcar, another brother, Mago moved on to command the Carthaginian forces in Spain. Defeat was suffered at Ilipa in 206 BC, however, and he soon retreated to Cádiz.
He then led a campaign to invade Italy (this time by sea) in 205 BC with 15,000 men. They sailed from Minorca to Ligures. He managed to capture Genoa, and held control of Northern Italy for three years.
Wounded in a battle in Cisalpine Gaul, he was recalled back to Carthage along with Hannibal to aid in its defence. Before arriving, however, he died at sea.