Sarpedon is the current Chapter Master of the Soul Drinkers Chapter of Renegade Space Marines who were exiled from the Imperium of Man as a result of their unwitting corruption by Chaos. Sarpedon was made Chapter Master by the acclamation of his Battle-Brothers after defeating Chapter Master Gorgoleon in an honour duel called the Shield-Rites. During the duel his body mutated, growing 8 arachnid legs. One was replaced with a bionic leg after losing it to Vorp, a Champion of Nurgle.
Sarpedon had a Force Staff made of the now rare material known as nalwood from the desert world of Tanith which dated from the period before Tanith's forests were reduced to wasteland. It was later replaced with the Howling Griffons' Lord Librarian Mercaeno's Force Axe, after the staff was broken in a duel with the Librarian. During the duel, Mercaeno psychically created his own version of Hell and recreated the Throne-Temple of Periclitor (a powerful Daemon Prince dispatched by Mercaeno himself). During the course of the duel, Sarpedon gained, lost and then regained control of Mercaeno's psychic world. Each time control of the psychic world shifted, so did the environment the two fought in. The worlds recreated included the Daemon World of Ve'meth, the Temple of Rogal Dorn aboard the Battle Barge Glory, and the world of Stratix Luminae.
Ultimately, the two returned to the original location, the deck of the Herald of Desolation (a Black Ship incorporated into the Space Hulk Brokenback). There the duel continued until Mercaeno emerged victorious. Fortunately for Sarpedon, before Mercaeno can deliver the death-blow, he was slain by the previous Chapter Master of the Soul Drinkers, Eumenes, wielding the Soulspear.
Most recently, Sarpedon was defeated in single combat by Captain Darnath Lysander of the Imperial Fists' 1st Company, and finally taken into Imperial custody aboard their Chapter flagship, Phalanx. Sarpedon and his wayward kin were forced to stand trial before a court composed of Imperial Fists' officers and representatives of the Inquisition as well as the Iron Knights, Crimson Fists, Howling Griffons, Silver Skulls, Doom Eagles and Angels Sanguine Chapters. During the trial, Imperial Fists Scouts investigated a world that was the supposed location of the mysterious Daenyathos to awaken him. Daenyathos was a Venerable Dreadnought, residing within an Adamantium Dreadnought sarcophagus. The Dreadnought then set in motion the last piece of an elaborate plan that had spanned over six millennia. His allies, the Daemon Prince Abraxes and Chaplain Iktinos and his flock, attempted to take over the Phalanx in the hope of using both the mobile fortress-monastery and the daemon's power to topple the Imperium.
The remaining Soul Drinkers refused to accept this, and while they managed to eventually banish Abraxes to the Warp, Sarpedon confronted Daenyathos, besting him in personal combat with the help of the sacred artefact called the Soul Spear. Sarpedon ripped the ancient warrior from his Dreadnought exoskeleton and then faced the representatives of the different Chapters and the Inquisition, who had defeated the remaining daemons. He issued to them a warning to beware of Chaotic corruption caused by following one's beliefs too blindly. He reminded them all to strive for the Imperial Truth, before dragging the withered form of Daenyathos through a Warp Gate and following the last two surviving Soul Drinkers into a final confrontation against the powers of the Warp. Sarpedon's final fate remains unknown to the Imperium.
- Abraxes - Daemon Prince of Tzeentch
- Daenyathos - Venerable Dreadnought of the Soul Drinkers, philosopher-warrior and ultimate agent of the Soul Drinkers' corruption by Chaos.
- Iktinos - Chaplain of the Soul Drinkers and secret agent of Daenyathos.
- Gorgoleon - Former Chapter Master of the Soul Drinkers
- Eumenes - Former Chapter Master of the Soul Drinkers
- Tellos - Former Assault Sergeant of the Soul Drinkers, turned servant of Khorne
- Ve'meth - Daemon Prince of Nurgle
- Vorp - Chaos Champion of Nurgle
- K'shuk- Interrogator of the Ordo Hereticus
- Mercaeno - Lord Librarian of the Howling Griffons
- Teturact - Adeptus Mechanicus secret project
- HellForged - Necron Overlord
- Soul Drinker Series:
- Soul Drinker (Novel) by Ben Counter
- The Bleeding Chalice (Novel) by Ben Counter
- Crimson Tears (Novel) by Ben Counter
- Chapter War (Novel) by Ben Counter
- Hellforged (Novel) by Ben Counter
- Phalanx (Novel) by Ben Counter