- "I am sorry, Altaïr. [...] But until certain matters are resolved it will not be possible for you to resume leadership of the Order."
- ―Abbas, taking leadership of the Order.[src]
The decline of the Levantine Assassins was a series of events which occurred in the Middle Ages, during which Abbas Sofian gained control over the Levantine Brotherhood of Assassins, following a coup d'état circa 1227. It resulted in Abbas overthrowing the Mentor Altaïr Ibn-La'Ahad, and subsequently forcing him into exile along with his son, Darim. During the twenty years of Abbas' reign, the Assassin Order fell into disrepute, until Altaïr eventually reclaimed his position in 1247.
In the meantime, Abbas set up and executed his manipulations. Firstly, he had Swami – his right hand man – kill Sef and leave the bloodied knife in Malik's room, so that on accusation, people would believe Abbas' account over Malik's. Following this, Malik was thrown into prison, and his interim leadership succeeded by a council - in line with the statutes of the Order should no leader be available - which was led by Abbas as chairman.
There, with the Master absent, his replacement imprisoned and his close followers removed, Abbas' tyranny and disdain left the Order and Masyaf to decay; bringing fear to the people and the Assassins, putting a stop to all training, and setting up Altaïr's downfall. Such was his negative influence that during his reign, the Templars retook the Templar Archive on Limassol and massacred the Assassins there, as Abbas provided no reinforcements.
After proving successful at killing Genghis Khan in 1227, Maria and Altaïr, both in their mid-sixties, slowly rode home on their horses, followed by Darim. Once inside the village, the atmosphere began to grow eerie; the younger children who did not recognize the Master rushed around excitedly, while the older villagers watched the three warily. The first to welcome them was Swami, who was still an Apprentice when Altaïr left. When Rauf, who Altaïr had initially requested to greet them in his letters, was mentioned, Swami told them he had died of a fever some years ago, at which Altaïr asked why he hadn't been informed; however, no explanation was given.
Assuming that their quarters had already been prepared, Swami responded again, negatively; instead, he directed them to a cabin on the western side of the fortress, telling them they would be accommodated there for the time being. Inside the citadel, even the guards acted like the villagers – keen to avoid all eye-contact, instead of welcoming them. When Maria asked where Sef was, Swami told them he had to travel to Alamut. Then, as Altaïr snapped and told Swami to get Malik at once, he informed them that Malik had been imprisoned, thus he could not.
He also let them know of the council that had been formed to replace Malik. A meeting with this council had been planned for the next day. Altaïr, worried about Sef, told Darim to head for Alamut as soon as Swami had left. This was according to Abbas' plans: to leave Maria and Altaïr unprotected, as Sef was dead, not at Alamut.
The council meeting
The council was composed of ten men including the chairman, all of whom sided with Abbas. The main reason for this council was to hear Altaïr's account of his journey to the East, an opportunity used by Abbas to humiliate the Assassin. During the meeting, Altaïr was informed of the reason behind Malik's imprisonment – that he had apparantly killed Sef, the Master's youngest son. This was a lie, however, to set the Assassin against Malik and enrage him, as well as purvey to the council that Altaïr was emotionally unstable and therefore unable to resume his leadership of the Order.
Later, after the meeting was concluded, Maria and Altaïr were huddled together in their room, reviewing everything that had happened and questioning what to believe. As doubt troubled Altaïr, he snuck his way to the Masyaf dungeons, driven by the curiosity of whoever was truly guilty for Sef's murder. There, he found Malik, emaciated and neglected in a cell, kept under watch by a sleeping guard. Altaïr brought him to the safety of his room, knowing finally that his old friend wasn't the killer.
Confrontation with Abbas
After finding his answers, Altaïr thought it was time to confront Abbas, to dispute the accusation made against Sef's murder. Of course, everything went in accord with Abbas' plans: when Altaïr and Maria were heading off to defy the accusal, he had Swami kill Malik, who had been left unprotected.
Confronting Abbas, Altaïr was instructed to hand over his Apple of Eden. As Swami approached to take it, he told Altaïr that Sef died believing his father had ordered his execution. Enraged, Altaïr used the Apple to make Swami kill himself. With Altaïr briefly distracted by Maria, Swami lashed out, stabbing her fatally. To end it, Altaïr quickly killed Swami with his Hidden Blade.
The Apple dimmed and Maria spoke her final words to Altaïr as he cradled her. In response to the events, Abbas ordered his men to kill Altaïr and take the Apple. Escaping into the village, Altaïr met with Darim, where together they fought off Abbas' men and escaped Masyaf.
A dark era had begun for Masyaf and the Order when Abbas' became its ruler. Right after the shift of power, a rebellion had erupted that consisted of the Assassins who remained loyal to Malik and Altaïr. The new ruler sentenced all the ringleaders to death, fearing a repeat of the insurrection. Abbas' paranoia made him stay in his tower day and night, imagining plots and planning who to put to death next, the tenets of the Creed crumbling around him just as the fortress itself fell into disrepair.
The training of Assassins had been stopped permanently, and the protection the Order once gave to the area was neglected, leaving the trade routes unguarded and open to criminal influences. Abbas had also been ruthless in demanding taxes from the villagers, often sending his Assassins to force people to pay; those who did not were either beaten up or cast out of the gates.
Many people loathed their leader secretly, hoping for someone to save them and return the Order to the state it once was. Deeply concealed within the village and the fortress, some people still learned the ways of the Assassins, one of whom was Malik's son, known as both Malik – to honor his father – and Tazim.
Return to Masyaf
Mukhlis was a tradesman on his way home to Masyaf, but exhausted by his journey, he reluctantly found a place to sleep by a well, unknowingly accompanied by a bandit, Bayhas. The next day the tradesman woke up with a blade to his throat, as he was then hauled up a tree, upside down, by a group of bandits, who were about to murder him. Luckily for Mukhlis, Altaïr had seen the commotion and took out one of the criminals, then fighting the other two, "Long Hair" and Bayhas.
The Assassin, being around eighty years old and unexposed to fighting for almost two decades, had lost his agility and stamina, and was almost killed by the bandits, but was eventually saved by Mukhlis intervening. Altaïr, bleeding heavily from his wounds, lost consciousness, but was quickly hauled over to a horse with which Mukhlis brought him to his home, where the old Assassin would be kept to restore his health.
Building the rebellion
Altaïr had been unconscious for a week, his wounds tended by Nada and Aalia, the family of Mukhlis. Word had spread amongst the people of the village, that their former leader had returned. Slowly but surely the old Master gained the trust of the villagers, using his knowledge and giving them hope for change. There, in the days that followed, Altaïr went to blacksmiths and weavers, telling them to make the devices he had seen in the Apple, one of which was the Hidden Gun. After Altaïr had met the young Tazim, they built up a small army of those inside the fortress which secretly favored Altaïr over Abbas.
Altaïr told his army not to kill anyone if it was absolutely necessary, as they made their way to the fortress where Abbas' loyalists had been stationed. There, the fight erupted within its walls, which was quickly won with no lethalities by Altaïr's side. Following his example, the archers that were placed on the ramparts, where Abbas resided, dropped their bows in protest so that the small army had an easy entrance into the citadel.
Inside, most of Abbas' people conceded immediately and switched their favor to Altaïr. Abbas however refused to relent, ordering the remnants of his loyalists to attack Altaïr – who at that moment, lifted his arm and shot Abbas with his Hidden Gun. Frightened by such an unexplainable act, even the toughest of Abbas' loyalists surrendered and joined Altaïr. There, Abbas shared his final words with his rival. Altaïr was once again leader of the Order.