Inquisitor de Fire had killed all but thirteen members of the 10th company but his primary target, captain Finn Keys, was still alive. The inquisitor had tracked him down to Devil's Den, a rocky, heavily forested area to the south east of Orbis hill. It covered an area of over 200 square kilometres and comprised the most challenging terrain on the entire second continent. Keys knew the place intimately and had a dozen of his best scouts with him. He also had advance warning of the inquisitor's plans. M'Kellan's message had got through.
Inquisitor de Fire left his base at Stolidus wood for Devil's Den with almost two hundred Stormtroopers and came back two weeks later with sixty six wounded and ninety one full body bags. Only one of those held the remains of an Exigator. The inquisitor came up with a new plan. He told the 16 captured scouts that they were free of the taint that afflicted many of the Exigators and that if they helped to hunt down Keys they would be able to continue their training and serve as a Marine in another chapter.
The scouts began a deadly game of cat and mouse with their former battle brothers. For four weeks the scouts stalked each other through the hostile terrain. Occasionally, Devil's Den was filled with the sound of gunfire, the triggering of traps and ambushes and the shouts and cries of desperate close combat. All this activity was separated by long periods of silence which sent the impatient de Fire into fits of apoplexy.
Keys lost seven of his loyal scouts before he killed the last of his former pupils. He strung the body up on a rock face as a defiant message for his inquisitorial nemesis. But the inquisitor had one last option. He called in an Eversor assassin.
Finn Keys was a skilled, cunning hunter who could survive for months at a time in enemy territory without support, but even he could not withstand the naked fury of an Eversor assassin. Two of his men were caught and brutally butchered. In a desperate gambit he lured the assassin into an ambush with himself as the lure. The gambit failed.
The Eversor discovered one of the scouts and shot him with his needle pistol before he could bring his heavy bolter to bear. Keys retaliated under covering fire from his last pupil. The assassin and the captain raced toward each other. The sniper's shot was true and hit the Eversor in the chest, cracking a rib and collapsing a lung. The assassin didn't break stride. He didn't even flinch.
He tore past Keys and raked his neuro-gauntlet across the marine's torso. The Eversor ignored the mortally wounded captain and bounded off after the sniper scout. He broke off after the scout disappeared in heavy brush and returned to Keys. Utterly dispassionately, he lopped off the captain's head. This was presented to de Fire as a trophy.
Despite that one missing scout de Fire declared his mission a success and left Insolitus, never to return. The Exigators now have no formal 10th company but they do occasionally return to Insolitus to take the best men from it's warrior lodges and induct them into the chapter.