During the Great Crusade he led the elite Justaerin Terminator Squad under First Captain Ezekyle Abaddon. Following the outbreak of the Horus Heresy, Kibre sided with Horus Lupercal, and the Justaerins escorted the Primarch during the Drop Site Massacre. Later, when Horus Aximand suggested reforming the Mournival, Kibre was Abaddon's proposed suggestion. He was a major Sons of Horus commander during the Battle of Molech.
Following Horus' wounding by Russ in the Battle of Trisolian and his fall into a coma after the Battle of Beta-Garmon, Maloghurst and Horus Aximand fought for power over what to do in the absence of Abaddon, who was busy fighting the Wolves. Kibre was reduced to a vicious guard dog during this tumultuous time, taking up guard near Horus' body and refusing any to be allowed entrance into Lupercal's Court. When Maloghurst, Kalus Ekaddon, and Tormageddon tried to heal the Warmaster, Kibre led the Justaerin in a vicious battle against Maloghurst's Luperci. However Maloghurst's gambit paid off, and after sacrificing himself Horus was restored. Before Kibre could finish off Ekaddon, Horus stood and picked the Widowmaker up by the throat. Terrified, Kibre was put back down and quickly obeyed the Warmaster's will once more. During the Siege of Terra Falkus and two of his Justaerin were one of the few non-Word Bearers to always be at Horus' side in Lupercal's Court. Falkus did little besides cling to his masters side like a loyal dog.
During the Siege of Terra, Falkus deployed on the surface on Terra along with the rest of the Mournival. He took part in Abaddon's subterranean assault underneath the Saturnine Gate in hopes of quickly winning the war. However the weakness under the gate was a trap set by Dorn, and upon burrowing under Saturnine in assault drills the Sons of Horus were ambushed by Kill-Teams led by Garviel Loken and Nathaniel Garro. During the desperate fight, Kibre and his Justaerin were wiped out by the a kill-team led by Garro. Kibre was bisected by Garro, revealing that he had become possessed by some sort of Warp entity which fled his body once it had been mortally wounded. Garro expressed pity for Kibre as he finished him off. Kibre's continued status post-Heresy is thus unclear.
Following the defeat of Horus and the banishment of the Traitors to the Eye of Terror, Kibre became a Possessed Chaos Space Marine.[6c] He was present at Maleum when it was devastated by the Emperor's Children during the Legion War. After this, he commanded the Cruiser Baleful Eye and a warband of the Sons of Horus known as the Duraga Kal Esmejhak. Upon hearing that Fabius Bile had cloned Horus, Kibre sought out the Vengeful Spirit and Abaddon with his allies Iskandar Khayon and Lheorvine Ukris.[6a] The trio eventually managed to find Abaddon, who reforged his new allies as the Black Legion and destroyed the Emperor's Children's fortress and slew Horus' clone.[6b]
- 1: Horus Rising (Novel) by Dan Abnett, Part One, Chapter 2
- 2: Fulgrim (Novel) by Graham McNeill, Chapter 25
- 3: Little Horus (Short Story) by Dan Abnett
- 4: Soul Hunter (Novel) by Aaron Dembski-Bowden, Chapter 7
- 5: Vengeful Spirit (Novel)
- 6: Talon of Horus (Novel)
- 7: Slaves to Darkness (Novel) Chapters 17–19
- 8: The Lost and the Damned (Novel) - Chapter 4
- 9: Saturnine (Novel) Part 3 Chapter 3