This Codex covers the lore and rules for the Thousand Sons Traitor Legion.
The lore section of this book briefly covers the creation of the Thousand Sons, their fall and their current state. The only real issue I have with this section is that I feel that the Rubric of Ahriman itself doesn’t get enough focus considering it’s one of the more import parts of the faction’s background. Other than this, the section is reasonably good with some nice lore for each of the Thousand Sons’ units, even if some of it is quite brief. There is, however, a decent amount of info on the new Sekhetar Robots who seem quite interesting.
The artwork and model photography are of the usual quality but, as with many other Codices, it would have been nice to see some of the alternate Thousand Sons colour schemes.
The rules in the book are standard for this edition with the usual Combat Patrol force, Detachments, Datasheets and Crusade rules. The Thousand Son’s Combat Patrol is reasonable if unspectacular, but I would have preferred some sort of Sorcerer leading it instead of a Daemon Prince (although that could have left it a bit underpowered). The Detachments available for the Thousand Sons are the combined arms Grand Coven, the Changehost of Deceit that allows Daemon allies, the Tzaangor focused Warpmeld Pact, the Rubricae Phalanx focusing on the rank and file of the Thousand Sons, and the vehicle focused Warpforged Cabal. All of these are quite usual for this edition, but I do like that the armoured vehicle Detachment makes a better effort at tying in with the themes of the Legion than some of the tank focused Detachments from of faction, adding some nice synergy between the Thousand Sons’ armoured vehicles and Sorcerers. The Dataslates in the book are also pretty standard for this edition. I do quite like the Brotherhood of Sorcerers Crusade rules that allow characters to advance up the ranks of the Thousand Sons’ Great Cults, gaining rewards and bonuses and they go.