Alpha 9-Thyrrc is an Adeptus Mechanicus Skitarii field commander. He was able to defeat a Tyranid fragment of Hive Fleet Behemoth that made its way into the Mechanicum-held Daugel Helix. Here the Mechanicus was able to use knowledge from the Tyran data-codex to give their Skitarii warriors a fighting chance. The Cohor commander Alpha 9-Thyrrc turned the tide by saturating a stratum of the atmosphere with gas from the planet's Promethium refineries. After his Onager's Neutron Laser sets the sky ablaze, each new wave of Tyranid spores are set aflame and incinerate those xenos planetside instead of reinforcing them. However this tactic is stored in a data-codex, brought back to the Forge World of Accatran and promptly forgotten.