Roman Army Wins but Doesn't Conquer City of Rome

Scenario: The Roman army, confident in their numerical superiority, prepared their battle lines in the Italian peninsula, in anticipation of a decisive and swift victory against the comparatively smaller Arab force. Unbeknownst to them, the Arab force was equipped with an advanced tactical strategy and knowledge of the terrain, which proved instrumental in their victory. The Roman army suffered massive losses, driving them away in full retreat. The Arab army, however, did not pursue a full conquest upon the City of Rome. Instead, they chose to celebrate their victory by parading through the Italian peninsula until their triumphant departure. In the aftermath of the battle, the Roman army was left decimated and demoralized, yet the City of Rome remained unscathed from the conflict.