Harlequin

"A corrupt nobleman underneath the mask, the Harlequin performs acts of terror among the people to further the Templar cause. The grin never leaving his face, he always keeps his dual Daggers at the ready... in case anyone is in need of an encore performance."

- Ubisoft description.

The Harlequin (real name: Cahin) was an Animi Avatar used by Abstergo Industries to train the recruits in their Animi Training Program. He could be obtained by pre-ordering certain editions of Brotherhood or after a system update and used two rondel daggers as his primary weapons.

Unique Moves
The Harlequin had several unique moves:

(Low Profile, Front)

The Harlequin neatly stabs his target under their chest, before flipping over their back while stabbing his victim in the neck, and then puncturing their right lung. Afterwards, the attack leaves his victim incapacitated and internally bleeding to death.

(Low Profile, Back)

From behind, the Harlequin stabs his target's waist, making them fall. Right as they begin to fall, he stabs them in the crevices of their neck with his daggers, one before the other, causing his victim to go limp. Their lifeless body then falls to the ground as he withdraws his daggers.

(High Profile, Front)

The Harlequin runs forward and jumps on his target, pushing them down in the process, before pulling out his two daggers and maniacally stabbing his victim in their torso several times. From the rapid movement of his attack, his target is pulled up slightly when they are punctured by his daggers, before their dead body slumps back to the floor after the final stab.

(High Profile, Back)

The Harlequin runs forward towards his target from behind, before performing a cartwheel and kicking his target in the side of the head, knocking them to the floor. As his victim lies on the ground, he quickly stabs his victim in the chest with one of his rondel daggers before pulling it out and storing it at his belt.

(Bench Kill)

The Harlequin walks up to his seated target and promptly stabs them in the stomach. As his target bends over, the Harlequin removes his dagger and stabs both of them in between his target's shoulder blades, before bounding over their back and hastily pulling his rondel daggers out. His victim stands upright, but then collapses forward, dead.

(Aerial Kill) 

The Harlequin leaps from a rooftop, removing his daggers while in mid-air, before landing on his target and rapidly stabbing their torso in a similar fashion to his High Profile frontal animation. The Harlequin then stands up, storing his daggers away and leaving his victim on the ground to die.

Customization
The Harlequin could be customized in several ways:

Colors Gear
 * Basic: Green and Blue
 * Extra 1: Red and Blue
 * Extra 2: Purple and Blue
 * Extra 3: Black and Blue
 * Advanced: Added vest (affected by color), buttons on the vest turned gold, added golden trim to gloves.
 * Superior: Longer tunic, added coat dove-like tails to vest and golden buckles to the foot of his boots.
 * Elite: Changed mask outlines from blue to golden.

Trivia

 * The Harlequin features in the release commercial of Assassin's Creed: Brotherhood, seen in the reflection of a puddle of water.
 * The Harlequin, as a character in history, has origins from the Italian Commedia Dell'Arte character Arlecchino, whose counterpart is Colombina, similar to the Hellequin.