The Gykon were an intelligent xenos species mentioned by the Warmaster Horus during the Great Crusade, when he debriefed Captain Garviel Loken of the 10th Luna Wolves Company. Horus mentioned the Gykon after Loken reported that one of his Space Marines became a Daemonhost to the Daemon known as Samus during a battle with the last of the insurgents on Planet 63-19.
Sources
- Horus Rising (Novel) by Dan Abnett, pg. 199