Asura is the name of a miniature officially announced by ArenaNet as a promotional offer available through various gaming magazines.
The "full size" creature corresponding to the miniature cannot be found anywhere in the game yet. It is assumed to belong to a future addition to the Guild Wars game series of some kind.
Trivia
Asura are demi-divine creatures in Hinduism and Buddhism. See the Wikipedia articles about Asuras in Hinduism and Asuras in Buddhism. The Guild Wars Asura may or may not be inspired by these.
