Masun

Masun was a resident and preacher of the village of Masyaf.

Biography
In 1191, Masun and a fellow Assassin, Jamal, defected to the Templar cause. When the Templars arrived at Masyaf the same year, after pursuing Altaïr Ibn-La'Ahad from Solomon's Temple in Jerusalem, Masun opened the gates for them and allowed them to lay siege to the village.

Soon after the attack on Masyaf, Altaïr discovered Masun's treachery through a letter that he had pickpocketed from the village's basket weaver. Upon interrogating Masun in a secluded area, the man revealed his allegiance to the Templars, to which Altaïr brought the traitor back to Al Mualim. There, Masun was given a final chance to repent, though the man remained defiant, and ultimately, the Mentor had no choice but to execute him.

Personality and characteristics
Masun appeared to be quite fervant at first sight, claiming that the Templars' goal was noble and that everyone should serve them. He was also quite persuasive, as he was able to advocate that Al Mualim was a bane on the village of Masyaf through his preaching skills, and had a streak of defiant loyalty, believing what he thought was right until his death.

Final words
Altaїr brought Masun before Al Mualim. Al Mualim killed Masun by stabbing him through the neck with a sword, piercing all the way to the weapon's hilt.
 * Masun: Enough! I yield, I yield!
 * Altaïr: Speak quickly then. I've no interest in your games. Why did you betray us, and who do you serve?
 * Masun: We serve the Templars. You should too. Their cause is just.
 * Altaïr: We?
 * Masun: Jamal. He told me of their plans. Asked me to open the gate.
 * Altaïr: You betrayed us. We, who called you brother and kept you safe from harm.
 * Masun: I did what I believed was right. And if you must kill me for it, so be it. I am not afraid to die.
 * Altaïr: Your fate is not for me to decide. It's Al Mualim who will judge.
 * Al Mualim: You stand accused of betraying our Brotherhood and opening the way for our enemies. How do you answer to these charges?
 * Masun: I deny nothing. I'm proud of what I did! My only regret is that they failed.
 * Al Mualim: I offer you a chance to repent. To renounce the evil in your heart.
 * Masun: It is not evil in my heart, but truth! I will not repent.
 * Al Mualim: Then you will die.

Trivia

 * The name Maṣūn (مصون) means "well-protected" or "safeguarded" in Arabic.
 * Ironically, the news of Masun's treachery was easy to discover, as it required only a letter to find out about, as opposed to the lengthier investigations that Altaïr had to perform for his later targets.
 * Masun was the only person that Altaïr did not kill after an interrogation, as all of the others were executed with the Hidden Blade shortly after the Assassin had extracted the information he required.
 * Masun possessed the same appearance as other Templar heralds that were interrogated by Altaïr in Jerusalem and Damascus.
 * Masun's apprehension and execution was not detailed in the Assassin's Creed: The Secret Crusade novel, as Altaïr traveled directly to Damascus for Tamir's assassination.

Reference

 * Assassin's Creed