Since at least 1510, Leandros' Templar forces had ruled the Syrian city of Masyaf, the historic seat of the Levantine Brotherhood of Assassins, after coming across Niccolò Polo's journal, "The Secret Crusade". From it, they learned of the Mentor Altaïr Ibn-La'Ahad's hidden library, and the keys required to unlock it.
After a year of searching the fortress, they finally discovered its entrance, but even after three months of attempted excavation to open the door, Leandros and his men were ultimately unsuccessful.
In 1511, Ezio Auditore da Firenze also journeyed to the city in search of the library, but was unaware of the Templar army that occupied it. After surprising him with an arrow shot to his right shoulder, Leandros' soldiers attacked him in great force, though Leandros himself only watched the battle from above.
Despite suffering many losses, his troops eventually managed to capture the Assassin, after breaking one of his Hidden Blades and cornering him with their halberds.
Following this, Leandros' forces later led the Assassin up to the castle's watchtower to be executed by hanging, as Leandros made sure to personally tie 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.
Ezio then leapt from the plank he was standing at, tightening the noose around Leandros' throat, and forcing his soldiers to cut him free. Once he recovered from the attempted strangulation, Leandros angrily ordered his men to pursue Ezio, who had landed safely below and escaped along the exterior of the tower.
Shortly after, Leandros left Masyaf by carriage, though Ezio soon caught up and lunged at his wagon, holding onto a trailing rope behind it and being dragged along the ground. After several attempts to try and shake the Assassin off, Leandros finally gave up, jumping onto the carriage of one of his soldiers riding alongside him, before throwing the unfortunate driver from the seat.
Recovering from the friction, and managing to pull himself to the back, Ezio took control of Leandros' previous carriage and continued the pursuit. Eventually, as they both jostled for position on a narrow mountain path, Leandros managed to outmaneuver Ezio and slip past him.
On command by the Templar captain, a guard then tossed a bomb underneath Ezio's carriage, propelling both it and him over the cliff edge with the explosion. However, just as Leandros commanded his men to guard the path from any intruders, the heavily wounded 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 or "throw [themselves] into the canyon", before heading into the village.
- Leandros：“What does it take to kill you, eh? Why will you not die?”
- Ezio：“Don't you ever stop howling?”
- ——Leandros to Ezio before his death, 1511.[来源]
Unbeknownst to Leandros, Ezio bested his men and silently pursued him through the village, using his Eagle Sense to follow Leandros' trail. Eventually, Leandros headed into a fortress, at which point Ezio revealed himself.
After taunting Ezio, Leandros boasted that there was nowhere for him to run, to which Ezio merely replied that neither of them would have the chance to escape, before severing the chain holding the portcullis open and blocking Leandros' reinforcements from arriving to help him.
From there on, Leandros fled up a tower, with Ezio in close pursuit. After making his way through the garrison, Ezio reached the top, where Leandros awaited him. Leandros then asked Ezio what it would take to kill him, which Ezio dismissed, before headbutting the Templar and 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. Once Leandros breathed his last, Ezio retrieved the journal of Niccolò Polo from his body.
Ezio! I'm going to dig your heart out with a shovel and feed it to you!
——Leandros yelling to the escaping Assassin, 1511.[来源]
Leandros was an able fighter, though he preferred using his soldiers to defeat his enemies. He also had a significant violent streak, 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 in order to save himself, and furiously telling a group to either follow his orders, or throw themselves off a cliff.
In physical appearance, Leandros was strongly built, though he had noticeable scars across his face, leading to one of his workers referring to him as "that ugly captain".
- Leandro's accent in the game is Medieval Greek, better known as Koine Greek, and it is very similar to this day to the Dodecanese accent found in the islands of Dodecanese, Crete and Cyprus.
- An early screenshot suggests that Leandros' model was originally meant to be used for Haras, the Levantine Assassin who betrayed the Order during the assault on Masyaf.
- In the novelization of the game, the circumstances of Leandros' death were altered. Ezio shot Leandros in the knee, and he bled to death after surrendering Niccolò Polo's journal.