From Lexicanum

Commander Shadowsun, also known as O'Shaserra, is the current Tau supreme commander. He was selected to replace the former commander, Commander Farsight. Shadowsun seems to be a more steadfast leader, more suited to the job of overseeing the Third Sphere Expansion. It was Aun'Va who selected Shadowsun, who was already an accomplished warrior from the deserts and jungles of the K'resh Expansion, where finally the Orks were contained and destroyed. She led several raids against a Tyranid splinter fleet and managed to enough damage on the hive ships that the Tau fleet lost no ships when they eventually were forced to fully engage the Tyranid fleet.

Under her leadership, the Tau Empire has again grown into the Third Sphere Expansion, formed five colonies in a halo around the original Sept worlds, including in the Damocles Gulf, Perdus Rift and much further afield. This success was due in part to the Imperium being distracted elsewhere and the Tyranids and Orks being temporarily contained.

Commander Shadowsun wears an XV22 Stealth Battlesuit into battle. She is accompanied by a Command-link Drone and 2 Shield Drones. She carries a Bonding Knife with her as well.

Sources

• ¹:Tau Empire miniatures gallery (accessed 2007.02.20)
• ²:Codex: Tau Empire (4th Edition)