Lok was the veteran Inquisitor whose taskforce uncovered the doom of the Adeptus Mechanicus research station on Beta Anphelion IV, where captive Tyranid specimens escaped their control and multiplied into a world-engulfing swarm. Valiantly battling the aliens, Lok was able to alert the Imperium before making his last stand, and was presumed killed either in the fighting or the ensuing Exterminatus. There are dark suspicions in the Ordo Xenos that Lok was martyr to the Radical theories of his superior, Inquisitor Lord Varius, who engineered the disaster as an experiment in anti-Tyranid warfare.