Yusuf Tazim

Yusuf Tazim was the leader of the Assassins' Guild in Constantinople during the early 16thcentury, and a Master Assassin in his own right.

When the Mentor of the Assassin Order, Ezio Auditore, arrived in Constantinople, a friendly rivalry developed between the two – though they both learned from the other's skills and abilities.

Yusuf introduced Ezio to the hookblade, a device that allowed the Assassins to utilize the many ziplines across the city's rooftops. He also gave Ezio a new, more powerful bomb in order to break the Great Chain, and the Janissaries' blockade.

Appearance
Yusuf wore tan Assassin robes and a headband, both with teal sashes. He wielded the Hidden Blade, the hookblade, and Throwing Knives, and was adept at the art of bomb-crafting.

Source

 * Game Informer: Characters of Assassin's Creed: Revelations