During the reign of the Cardinal-Duke Thrackos, the armed might of the Agrippa Sector was directed against the Eldar in the Scylla sub-sector. The campaign floundered when Kitchener's advance was cut off at Kali. Unexpected but timely reinforcement by the Twelvers turned the tide, and an Imperial victory was carved out.

Future revalations of Thrackos' treachery during the so-called Thrackos Scandal has lead many to believe that the Scylla crusade was an opening ploy of his to weaken the Agrippa Sector for attack by the forces of Morpheus Vrool.