From The Stargate Omnipedia
hunter and assassin, sent by the System Lords
to eliminate those who oppose them. Ashraks are highly-trained and extremely capable at what they do, and usually possess the most advanced technologies (including the Hara'kesh
) for carrying out their missions.
In the Line of Duty - An Ashrak is sent to kill the Tok'ra Jolinar of Malkshur, finally succeeding in a Cheyenne Mountain prison cell.
Fair Game - Major Carter learns that it was the System Lord Cronus who sent the Ashrak to kill Jolinar.
Allegiance - An invisible Ashrak causes the destruction of a Tok'ra base, and causes havoc between the Tok'ra and rebel Jaffa when he follows them through the gate to Earth's Alpha Site.