The defense of Masyaf was an event which came about as a direct result of the disastrous mission to recover the Apple of Eden from Solomon's Temple. The Grand Master of the Knights Templar, Robert de Sablé, led his army into besieging the Assassin stronghold of Masyaf, in an attempt to destroy the Levantine Assassins and end their interference in Templar affairs.
Call to arms
Upon returning to Masyaf from his mission at Solomon's Temple, Altaïr Ibn-La'Ahad met with his master, Al Mualim, and detailed the events that had transpired there. Stating that Robert de Sablé was not alone in the temple, Altaïr confessed he was unable to retrieve the treasure as commanded, enraging Al Mualim.
Suddenly, Malik Al-Sayf, one of the two Assassins that had accompanied Altaïr to the temple, arrived cradling his severely injured left arm. He viciously berated Altaïr for the latter's reckless actions at the Temple, blaming him for the death of Kadar, Malik's younger brother. He also claimed that Altaïr's actions had nearly cost the Assassins victory, but he himself had managed to retrieve the treasure in Altaïr's stead. Though he was successful in his task, Malik warned Al Mualim that he had been pursued by de Sablé's men, and they would soon be upon Masyaf.
At that moment, an informant arrived and warned Al Mualim of invaders attacking the village; the Master responded by dispersing the Assassins into the village in order to drive them out. As Al Mualim dismissed the informant, he confronted Altaïr, stating that his punishment would have to wait. As Altaïr left the fortress, he met with Rauf, who requested his aid in distracting the Templars while other Assassins guided the village's civilians inside the fortress.
Making his way into the village, Altaïr fought against the Templar forces attacking it and its people. Despite their valiant effort, the Masyaf guards were eventually overrun by the Templar army, and were forced to retreat back into the fortress.
Men without fear
As the last of Masyaf's citizens and guards entered the fortress, Rauf requested that Altaïr come with him to the top of the tower. Once there, Altaïr witnessed de Sablé and his army arrive at the fortress gates, demanding Al Mualim's surrender. Executing a hostage in an effort to intimidate Al Mualim, de Sablé claimed he would starve the Assassins out. However, Al Mualim was not fazed, and replied that his men were not afraid of death. As proof, he ordered the Assassins at the top of the tower to leap into the ravine below.
As commanded, Altaïr and his comrades performed simultaneous Leaps of Faith from the tower. However, they landed in haystacks below rather than falling to their deaths, though one Assassin injured his leg in the process. Tending to the man, Rauf told Altaïr to proceed alone and complete their mission. Altaïr complied, making his way over long wooden beams along the gorge and scaling a nearby tower.
Once inside, he cut through a rope securing a pile of logs, releasing them onto the Templar forces below. Taken by surprise, many of de Sablé's men were crushed, and the army quickly retreated.
Into the void
After routing de Sablé's army, the Order began to repair the damage done to the village and collect the dead bodies of their brethren. Back at the fortress, Al Mualim recognized Altaïr for his efforts in forcing back the Templar army, but also berated him for his previous actions which ultimately led de Sablé to their doorstep. He then commanded two disciples to restrain Altaïr, and lectured him on his disregard for the tenets of the Creed.
Altaïr still showed signed of disregard for the higher authority of his master, interrupting as he spoke about the first tenet. Al Mualim struck Altaïr across the face, scolding him for speaking out of turn. He then detailed how Altaïr had broken each of the three tenets of the Creed, thereby risking the safety of the Brotherhood. He concluded that he could not abide a traitor within their ranks; Altaïr claimed that he was no traitor, but Al Mualim stood by his decision, bidding Altaïr go in peace before stabbing him in the stomach.
After a short while, Altaïr awoke in front of Al Mualim's desk, alive and well. Confused, he asked how he was alive after feeling "death's embrace", to which Al Mualim replied that he had seen and felt only what he was meant to. Now he could be born anew and reinstated into the Order, enlightened once more to the way of the Assassins. He was then demoted to the rank of novice, void of any weapon, and given a new task: find the traitor who opened the gates of Masyaf to the Templars, proving himself capable in the ways of the Assassin Order.