Thunder Kings
Summary of Legion XXI
Generalists, Repentant, Not!Celts Even-tempered, proud, and noble. The Thunder Kings took the Heresy badly, with more than half of their legion fighting for Hektor and his Traitors. They are now repentant, trying to quietly clean up their mess. They are renown for taking a cautious, methodical approach to warfare, and favour combined armed tactics over any single focused doctrine.
Legion Tactics
Legion Equipment


It is rumored that the Thunder Kings claim descent from similar genetic stock as the Thunder Warriors of old, and are simultaneously the subject of interest and revile as a consequence. They are larger than the majority of other Astartes, yet exhibit no other outward signs that’d betray such lineage.
Legion Doctrine
It is rumored that the Thunder Kings claim descent from similar genetic stock as the Thunder Warriors of old, and are simultaneously the subject of interest and revile as a consequence. They are larger than the majority of other Astartes, yet exhibit no other outward signs that’d betray such lineage.
Appearance
Youth
The Coming of The Emperor
The Great Crusade
The Heresy
During the Heresy, seven of the twelve tribes abandoned the Emperor and Brennus, heading towards Terra to assist Hektor Cincinnatus. Four of the remaining tribes set out in the same direction, assisting loyalist forces in various skirmishes and battles in the vicinity of the Sol system. It would be almost a year before Brennus lifted himself from Alessia, burning the world behind him, and took his last remaining tribe--his personal one--with him to Terra.
Post-Heresy
In the modern era, the tribal structure has been disbanded, and the Chapter no longer recruits from a single world. The loyalist tribes were instead broken off into their own individual Chapters, and are known to maintain close ties to the original Thunder Kings--who are all of Brennus’ original tribe. The Chapter is now mostly Codex Astartes adherent, at least with regards to organization, though it still maintains more Marines than is considered standard--owing to its extended garrison duties in many locations. Most notable is still their fondness for unified tactics, and it is unsurprising to see the Thunder Kings working alongside their brother chapters or with regular Imperial forces in the conduct of a combined front against a greater enemy.
Following the voluntary burning of Alessia, the Thunder Kings instead now recruit from a multitude of planets spread out over a gauntlet of stars known as the Soctis Cluster. With several black holes orbiting the periphery of the cluster, the habitable planets scattered throughout the Cluster are habitually bombarded by erratic seasons, exotic radiation, and altogether experience harsh conditions. It is from these worlds that the Thunder King recruits are drawn, with a permanent garrison maintained on each one.