Gawain’s killer in the Italian La Tavola Ritonda.
Turinoro was the count of Cartagina (Carthage) and the brother of the Pope.
He had been knighted by Lancelot, so when Arthur went to war with Lancelot, Turinoro journeyed to Benoic (Benwick) to help his friend. He encountered Arthur when the king was on the way back to Britain to deal with Mordred’s insurrection. Turinoro and his forces engaged Arthur’s men.
According to Tavola ritonda Turinoro slew Gawain, but was killed himself in the fighting.
Source
La Tavola Ritonda | 1325–1350