Worgen

Worgen is a race introduced during the Cataclysm expansion. Worgen is a race only in the alliance faction mainly because they are werewolves and start of as a human. In the Worgen storyline humans are trying to kill the Worgen, but it all goes bad when the player goes into a cellar. The guy in the cellar turns into a Worgen and bites the player. The transformation does not happen till a bit later, but when it does the player ends up in a stockade to get out only if they help the Humans. The Worgen spawn place is a dark town complete covered with humans and Worgens coastally fighting each other. The Worgen racial abilities are running wild allowing the Worgen goes all four hands and feet to run which is their mount, two forms allows the Worgen to freely shift from Human to Worgen; however, Worgen can not fight in the human form, aberration makes any curses and disease affect them for less time, darkflight is a ability that makes the Worgen run faster for a short amount of time, flayer allows Worgen to skin faster, and viciousness they fight with ferocity and gain a bonus to critical strikes. The Worgen story line is going around the country trying to kill all the Worgens.

The initial Human form fighting against Worgens which are seen as the villains in this story. 

 Waking up in the stockade when the player becomes a official Worgen, and have to say that they wont kill a Human to get released.