Beloth gained infamy during the Great Crusade for purging billions of humans on Serenity Alpha after condemning their decadent lifestyle that relied completely on robotics and technology. An extremely ambitious individual, Beloth was eager to become more a commander than a conduit, to achieve a higher purpose standing at the side of Lorgar Aurelian as Erebus and Kor Phaeron did. First Chaplain Erebus and Beloth's own Dark Apostle Maloq Kartho encouraged his ambitions.[1a]
During the Battle of Calth, Beloth was one of the Force Commanders selected for the assault, charged with taking and securing Lanshear for the Word Bearers.[1a] When Captain Remus Ventanus lead the Ultramarines 4th Company into Lanshear to secure a cogitator with a kill-code, Beloth soon realized that they were attempting to achieve something specific and unleashed Titans, Terminators, and the Gal Vorbak upon the Ultramarines.[1b] Before his forces could finish off the 4th, reinforcements from the Ultramarines 19th, 111th and 112th Companies under Captain Aethon and Sergeant Anchise, Titans and Land Raiders under Tetrarch Tauro Nicodemus, and the Neride 41st under Tetrarch Eikos Lamiad and the Contemptor Pattern Dreadnought Telemechrus arrived to reinforce Ventanus. The strength and coordination of the reinforcements shocked Beloth's forces and two of his senior captains were killed by Telemechrus. While this effectively served to concentrate Hol Beloth's victims into one place, the tide soon turned on the Word Bearers when Magos Meer Edv Tawren took control of the planetary defense grid and opened fire on the Word Bearers from orbit, obliterating most of Beloth's forces.[1c]
His ambitions shattered, Beloth retreated with the rest of his surviving forces into the Uranik Radial arcology as Calth's sun turned radioactive. Safely underground he brooded on his failure until Maloq Kartho goaded him into joining the Underworld War, taking the fight to the Ultramarines once more. Beloth joined a strike team led by Kartho which recovered a virus bomb from the surface and followed Kartho up a damaged skyscraper from which the two of them could see Remus Ventanus's forces attacking the stronghold of Foedral Fell. Kartho then detonated an atomic bomb which wiped out the Uranik Radial, sacrificing Beloth's forces to further his bid for daemonhood and collapsing the skyscraper into a deep cave system. Remarkably Beloth survived the fall and was able to join Kartho's assault on Arcology X, stronghold of Ventanus's forces which had been left lightly defended whilst Ventanus took his forces to assault Foedral Fell. During the battle Beloth mutated into an unstoppable daemon, and was only slain when Ventanus detonated a pair of grenades within his body and revealed Beloth's subsumed athame, which Ventanus used to slay the mutated former commander.
- 1: Know No Fear (Novel), by Dan Abnett
- 2: The Shards of Erebus (Short Story) — Mark of Calth (Anthology), by Guy Haley
- 3: The Horus Heresy Book Five pg. 252
- 4: Calth That Was (Novella) — Mark of Calth (Anthology), by Graham McNeill, [Needs Citation]