Leandros

"Could it be that you are every bit as deadly as the legends say? Or am I in charge of an army of drunks swinging sticks?!"

- Leandros to Ezio, infuriated by his persistence.

Leandros (died 1511) was a member of the Templar Order, and the Captain of a small Byzantine garrison stationed in Masyaf.

Search at Masyaf
Since at least 1510, Leandros' Templar forces had overrun the former Assassins' former fortress in Masyaf, Syria, and Leandros had acquired "The Secret Crusade," the journal of Niccolò Polo, which he kept with him at all times.

After subsequently discovering the sealed entrance to the library of Altaïr Ibn-La'Ahad, he assigned his men and workers to discover a way to break through the door, though they were unsuccessful.

When the Mentor Ezio Auditore da Firenze visited the city in 1511, Leandros' soldiers attacked him in great force, with Leandros himself only watching the battle from above. Despite suffering many losses, they eventually managed to capture him.

Leandros' forces later led the Assassin up a tower in the fortress to be executed by hanging, and Leandros personally tied the noose around Ezio's neck. However, as soon as he did, Ezio lunged back at him and managed to wind the rope around his would-be executioner's neck.

The Assassin then leapt off the plank, tightening the noose around Leandros' throat and forcing the guards to cut him free. As he recovered from the attempted strangulation, Leandros yelled to his men to pursue Ezio, who had escaped along the exterior of the tower.

Shortly after, Leandros left Masyaf by carriage, though Ezio managed to keep up by holding onto a rope tied to the wagon. After several attempts to shake the Assassin off by driving over rocks, bushes and a river, Leandros finally gave up, and leapt onto the carriage of one of his men.

Ezio took control of Leandros' previous carriage and continued the pursuit, an eventually, as they rammed each other on a mountain path, Leandros managed to outmaneuver the other and slip past him.

A guard then tossed a bomb under Ezio's carriage, throwing both it and him over the cliff edge. Just as Leandros commanded his men to guard the path from any intruders, Ezio managed to climb up the cliff and face the soldiers again.

Seeing that the Assassin was injured, Leandros ordered his men to bring him his head, before fleeing into the village.

Death
Unbeknownst to Leandros, Ezio bested his men and silently pursued him through the village. Eventually, Leandros headed into a fortress, at which point Ezio revealed himself.

After taunting Ezio, Leandros boasted that there was nowhere for Ezio to run. Ezio simply replied "Not for me, and not for you!" before severing the chain holding the portcullis open, and blocking Leandros' reinforcements.

Leandros fled up a tower, with Ezio in close pursuit. Once they both reached the top of the tower, Leandros asked Ezio what it would take to kill him, to which Ezio asked if Leandros ever stopped howling, before stabbing him with his hidden blade.

As Leandros lay dying, he revealed that his fellow Templars were already closing in on the Masyaf Keys, with which they could find the location of the Grand Temple. As Leandros breathed his last, Ezio retrieved the journal of Niccolò Polo from his corpse.

Personality and characteristics
"Ezio! I'm going to dig your heart out with a shovel and feed it to you!"

- Leandros yelling to the escaping Assassin.

Leandros was an able fighter, though he preferred using his soldiers to defeat his enemies. He was rather violent as well, threatening his workers with death should they try to leave.

He also held little respect for the lives of his men, throwing one from a moving carriage to save himself, and telling a group to either follow his orders, or throw themselves into the canyon.

In physical appearance, he was strongly-built, though had a noticeable scar across his face, leading to one of his workers once referring to him as "that ugly captain."

Final words
This will do no good, not now. We have found one of the Masyaf keys already, and are closing in on the rest.'' Requiescat in pace, bastardo. (Rest in peace, bastard.)
 * Leandros: Well, the old hound still has a bite.
 * Ezio: The book you carry. Where is it?
 * Leandros: ''Ah! Niccolò Polo's journal?
 * Ezio: What is in that library is not for you. Not the Templars.
 * Leandros: Ah, you can have Altaïr's books, Ezio. We only want guidance. We only want directions... to the location of the Grand Temple.
 * Ezio: Grand Temple? Tell me more. Now!

Source

 * Assassin's Creed: Revelations