Hannibal
In 212 BC, plotters in Tarentum let Hannibal into the city. They then blew the alarm with some Roman trumpets. This let Hannibal's troops pick off the Romans as they stumbled into the streets. Hannibal told the Tarentines to mark every house in which Tarentines lived so that they would not be looted. Even with the looting, the citadel held out. That stopped Hannibal from using the harbuor, and Rome was slowly gaining ground over Hannibal. In the same year, he lost Campania.