Thief

The Thieves were one of the factions-for-hire during the Renaissance, alongside courtesans, mercenaries and the Romanies. They were adept free-runners, and possessed a number of guilds in different cities.

Several guilds, including the Venetian guild and Roman guild, were allied to the Assassin Order. As such, they possessed a measure of virtue; refusing to steal from the poor, and fighting to defy the local, corrupt nobility.

However, a number of thieves were independent of the Order. The Cento Occhi in particular were allied to the House of Borgia, and sought to counteract the Assassins. Several pickpockets chose to steal freely from Assassins as well.

Florentine (and later, Roman) thieves were led by La Volpe, Venetian thieves were led by Antonio de Magianis, and the Rome-based Cento Occhi were led by Lanz.

History
From as early as when a thief helped to save his life by urging him to run from the guards at his family's execution, Ezio Auditore da Firenze both helped, and enlisted aid from thieves on several occasions.

Thieves were often the most well-informed factions of the cities, and were thus able to provide Ezio with information on targets and other events in their district. In Florence in 1478, La Volpe made use of one of his thieves to lure Ezio to him, after which he gave him details on how to locate Francesco de' Pazzi.

In 1481, after assisting Rosa, one of the members of the Venetian guild, Ezio allied with the thieves in order to infiltrate the Palazzo della Seta. Together, he and the thieves successfully claimed the building and assassinated Emilio Barbarigo in 1485.

Some time prior to 1499, Paganino, a member of the Venetian guild, betrayed his allies and became a spy for the Templars; passing them vital information on the Assassin Order, and their base in Monteriggioni. At the opening of the new year in 1500, his actions eventually led to the Fall of Monteriggioni.

Upon traveling to Rome, Ezio allied his newly-founded Assassins guild with La Volpe's thieves. After aiding them in establishing their headquarters in La Volpe Addormentata, he learned of their close rivalry with the Cento Occhi thieves.

In contrast to the Assassin-allied thieves, the Cento Occhi stole from the poor, and terrorized the civilians of Rome. At La Volpe's request, Ezio aided in repressing them, fighting in brawls alongside La Volpe's thieves, sullying the Cento Occhi's reputation with the Borgia, and killing the guild's leaders.

In 1511, Ezio visited the Constantinople Thieves Guild and learned they were having troubles due to a snitch tipping off guards to their activities. Ezio learned Lord Halim was bribing the snitch and assassinated him.

Characteristics
Though he usually worked alongside the guilds to suppress Templar-control of a city, Ezio also hired thieves on the streets, offering them money in return for assistance. Unlike the other hired factions, they could easily follow the Assassin along rooftops.

The thieves could help Ezio by distracting any soldiers guarding high-profile locations, such as Banks or other restricted areas. They often did so by attacking or taunting the men, and subsequently luring them away. Should Ezio engage in a fight as they followed him, they would always help him defeat his enemies as well.

After he had competed alongside them in several challenges, the thieves of Rome and Constantinople began to further assist Ezio by pickpocketing money for him whenever he hired them.

Combat
Thieves were lightly armed, carrying only a dagger (or a sword on rare occasions) and wearing very light armor. This allowed them to follow Ezio in many of his acrobatic moves, though did not offer much protection in combat.

They resorted to speed and agility in combat, dodging and countering enemy blows much like Agile guards. As such, they were usually only vulnerable to well-protected guards, such as Brutes and Seekers.

Venice

 * Antonio de Magianis
 * Ugo
 * Rosa
 * Franco
 * Paganino

Rome

 * La Volpe
 * Claudio
 * Trimalchio
 * Paganino
 * Aldo

Achievements
The achievement "Steal Home" is awarded for winning a race against any thief in Assassin's Creed II. In Assassin's Creed: Revelations, once Ezio fulfils the thief challenges and unlocks thief looting, he can earn a achievement for a hired group of thieves looting the dead guards he leaves in his wake.

Trivia

 * The memories where thieves use swords instead of daggers include "Cleaning House," and "Who's Got Mail?"
 * Like guards, in Assassin's Creed II, thieves are generally better equipped in Venice than they are in Florence.
 * The boy in the mission "Human Cargo" is dressed like a thief.
 * In Assassin's Creed: Brotherhood, Ezio can lock onto thieves that signal the start of a Thief Assignment and perform execution moves on them. After appearing to die, they soon recover and get back up.
 * In Assassin's Creed: Project Legacy, it's possible to train Cento Occhi thieves and use them in missions.