Downsizing

Downsizing is a memory from Assassin's Creed: Brotherhood

Description
Ezio comes across a thief and hears him out. The thief tells Ezio about a traitor in the Thieves Guild, who is actually a high-ranking member of the rivalling gang, the Cento Occhi. He asks Ezio's help to get rid of this traitor. Ezio agrees and follows the thief through Roma, before finally arriving at their destination. Once there, Ezio is ambushed by Borgia guards. He kills them all, before killing the traitorous thief.

Dialogue
Ezio walks up to the thief.
 * Thief: Ezio, one of the Cento Occhi (Hundred Eyes) leaders has worked his way into our own guild! He is an accomplished liar, responsible for the deaths of many of our brothers. Come, I will lead you to him.

Outcome
Ezio kills the traitorous thief, along with the Borgia soldiers that assisted him in the ambush.

Trivia

 * To get 100% synchronization, Ezio must kill the traitor with his hidden blade.
 * The thief tells you the traitor is an accomplished liar. This is later proven when it turns out he was the traitor all along.