|This article is about the Titan Legion, for the short story by John French see Ordo Sinister (Short Story)|
|Colour Scheme||Info||Legion Symbol|
|Name:||Titanicus Terranic Ordo Sinister|
|Alternative names:||Left Hand of the Emperor, Nightmare Titans|
|Colours:||Green-Black Verdigris and Silver|
|Strength:||20 Warlord-Sinister Psi-Titans (M31)|
|Motto:||Pavore Dominetur (the rule of terror)|
The Ordo Sinister has a unique status within the Imperium, for it is they alone who are able to employ terrible weapons forbidden to even Primarch and Planetary Governor alike. Many of these technologies are of the Sinistrum category, those weapons designed to amplify the powers of a Psyker, often at the cost of their own life. These devices have since been installed upon Warlord Titans of the Ordo Sinister, forming psychic god-machines known as Psi-Titans.
It is not known when exactly the Ordo was formed, but they first gained prominence in 967.M30 when the Emperor demanded that 25 Warlord Class Titans be issued to Terra for an unknown reason. Later, a single one of these Titans, fashioned in terrifying livery, managed to subjugate the entire rebellious world of Skagan-VI without firing a single shot. Later during the Defence of Helioret the Ordo Sinister defeated the insane Eldar Corsairs and Wraith Constructs of Craftworld Magc'Sithraal, a foe even Sanguinius and the Blood Angels could not bring to heel alone.
- 967.M30 Writ of Compulsion
- Subjugation of Skagan-VI - Chamber Polaris, 1 Warlord-Sinister Psi-Titan, first known deployment.
- Defence of Helioret - 3 Warlord-Sinister Psi-Titans.
- 005.M31 Battle of Prospero - Chamber Occedentalis, 5 Warlord-Sinister Psi-Titans.
- 005-010.M31 War Within the Webway - Chamber Borealis, at least 1 Warlord-Sinister Psi-Titan.
The Ordo Sinister operates from four independent Chambers, each comprising five modified Warlord Psi-Titans and operating from a "fortress-crypt" on Terra. These fortresses are based in the Occendentalis, Orientalis, Polaris, and Borealis regions of Terra.
- Borealis-Thoon - fought in the War Within the Webway.
- Polaris-Albedelach - The King of Terrors, subjugated Skagan-VI.