Who is the assassin in avatar last airbender?

There isn't one specific assassin in *Avatar: The Last Airbender*. While there are characters who carry out assassinations, like the Dai Li (the Earth Kingdom's secret police) or the Order of the White Lotus (who sometimes act as spies or assassins), they aren't defined by a single figure.

However, if we're looking for a character most associated with assassination attempts, it would likely be Azula, the Fire Nation princess.

* Azula's tactics: She employs ruthless tactics and often uses her bending skills to injure or even kill her opponents.

* Examples: She targets Zuko, Katara, and Aang with deadly force on multiple occasions.

So, while no single character is explicitly an "assassin" in *Avatar: The Last Airbender*, Azula's actions and tendencies make her the closest to fitting that description.