Battle of the Trench enemy in the open (which led to victory at Badr), and waiting for them inside the city (a lesson learnt from the defeat at Uhud) were both suggested. Ultimately, the outnumbered Muslims opted to engage in a defensive battle by digging deep trenches to act as a barrier along the northern front. The tactic of a defensive trench was introduced by Salman the Persian. Every capable Muslim in Medina including Muhammad contributed to digging the massive trench in six days. The ditch was dug on the northern side only, as the rest of Medina was surrounded by rocky mountains and
Battle of al-Qādisiyyah and led a group of Mubarizuns, from his Syrian contingent who were also the veterans of Battle of Yarmouk, through the Sassanids' right center towards Rostam's headquarter. Rostam again personally led a counterattack against the Muslims, but no breakthrough could be achieved. At dusk, the two armies pulled back to their camps. On 18 November, Rostam wanted a quick victory, before more Muslim reinforcements could arrive. The Elephant corps was once again in the front of the Sassanid army, giving him the advantage. Pressing this advantage, Rostam ordered a general attack along the Muslim front, using his full force. All