In the Segmentum Solar, Space Marines from the Invaders 2nd Company investigate a reported Eldar sighting on Bissan. They are attacked by Word Bearers who arrive by Strike Cruiser. In the ensuing battle, a squad of Devastator Centurions staunchly defend their battle-brothers from atop the ruins of an old exodite settlement, eventually destroying many tainted tanks, Forgefiends and Helbrutes.
The Invaders Chapter launches an all-out assault on their attackers, eventually driving the traitors from the planet. The victory is attributed to the tactical awareness of Centurion Sergeant Thynor; he downs a Word Bearers Thunderhawk before the reinforcements aboard can deploy, turning the battle. Modest, he accredits the success to the precision afforded by his Omniscope.