Altair is the fave of several developers...
Mohamed Gambouz: Art Director on Assassins Creed Unity (also worked on Assassins Creed, Assassins Creed 2, Assassins Creed Brotherhood and Assassins Creed 3)
"Im hesitant between Ezio and Altar but as a character Id go with the later, his personality has a lot of depth and his achievements and endeavours had big impacts on the world and people around him. In terms of the look, the purity and solid statement of Altairs design makes him the foundation of the visual appeal of all Assassins that followed."
Raphael Lacoste: Art Director of the Assassins Creed Brand (also worked on Assassins Creed 4 Black Flag, Assassins Creed Revelations and Assassins Creed)
"Difficult choice, as they all have their own personality, story and setting, which are all memorable and unique. I would still say that my favourite one is Altair, because first I am a nostalgic guy ;-), and secondly I loved to evolve with him in the contrasted, varied world of Assassins Creed. Altar is extremely charismatic and unique. He is for me one of our best achievements in character design and animation."
Vincent Pontbriand: Senior Producer on Assassins Creed Unity (also worked on Assassins Creed, Assassins Creed 2 and Assassins Creed Brotherhood)
"My favorite Assassin is Altar. He was the first one, the warrior, the driven, loyal and dedicated Assassin. Hes the definition of badass, and became an instant classic. Of course he was followed by the more charismatic and relatable Ezio, but Altar was the one for me."
Darim Ibn-La'Ahad (Assassin's Creed: The Secret Crusade novel/Assassins Creed Revelations)
The eldest son of Altair and Maria. He quells a Mongol rebellion by - wait for it - assassinating Genghis Khan in one of the AC novels.
Sef Ibn-LaAhad (Assassin's Creed: The Secret Crusade novel)
The youngest son of Altair and Maria, and propagator of Desmonds maternal line. He stayed in Masyaf when the rest of his family went on a mission to assassinate Genghis Khan to take care of his wife and daughters. Like any good dad in fiction, he dies as a result, in Abbas Sofians coup d'etat.
Rashid ad-Din Sinan/Al Mualim (Assassin's Creed)
Altair's mentor and the patriarch of the Assassin Order. He briefly defected to the Templar cause before stealing their Apple of Eden and flipping everyone the metaphorical bird.
Ahmad Sofian (Assassin's Creed: The Secret Crusade novel)
One of Sinan's spies and the father of Abbas Sofian. He sadly committed suicide out of shame after being captured by enemy combatants and traded for Altairs father, Umar Ibn-LaAhad. Yup - Altairs father was an Assassin too.
Malik Al-Sayf (Assassin's Creed)
Head of the Assassin's Bureau in Jerusalem, and trusted friend of Altair. Although their relationship was rocky after Altairs neglect got Maliks little brother killed and his arm chopped off, he eventually came to respect Altair and signed on as his right-hand man.
Kadar Al-Sayf (Assassin's Creed)
Maliks younger brother and a novice Assassin, Kadar was present during the ill-fated mission to retrieve an Apple of Eden from Solomons Temple at the start of the first Assassins Creed. He was killed in the chaos after Altair exposed their position to the Templars.
Abbas Sofian (Assassins Creed: The Secret Crusade/Assassin's Creed: Revelations)
A childhood friend of Altair and son of Ahmad Sofian. He grew resentful when Altair informed him of Ahmads suicide, believing that his friend was trying to slander him. Abbas hatred persisted into adulthood, when he launched a coup d'etat in Altairs absence.
Swami (Assassins Creed: The Secret Crusade/Assassin's Creed: Revelations)
Abbas dull but brutal lcky. When Abbas ordered Sefs death, Swami was the one to do the deed. Altair killed him with the Apple of Eden upon finding out the truth, but not before Swami dealt a fatal blow to Maria Thorpe.
Qulan Gal (Assassin's Creed: The Secret Crusade novel)
A Mongolian assassin who helps Darim (Altair's son) kill Genghis Khan. Wears an excellent Mongol beard, and is an expert horseman.