[[Image:CastellaxArt.jpg|thumb|right|200px220px|Castellax Class Robot]]'''Castellan Class Robots''' were a type of war [[robot ]] deployed by the [[Legio Cybernetica]].{{Fn|1}}

The most numerous pattern of Castellan Class Robot are the '''Castellax Battle-Automata'''{{Fn|2}}, which are designed primarily for siege and shock assault operations and are known for a particularly aggressive [[Machine Spirit]].{{Fn|2}} These machines were the mainstay of the Legio Cybernetica and served as the elite defensive formations of many [[Forge World]]s. Castellax Robots were equipped with a shoulder-mounted [[Mauler Bolt Cannon]], [[Multi-Melta]], or [[Darkfire Cannon]] and twin [[Power Fist]]s with Shock Chargers and built-in [[Bolter]]s or [[Flamer]]s. These fists could be replaced with [[Power Blade]]s. In addition these weapons, they sported the [[Atomantic Shielding|Atomantic deflector shield]] that was seen on the [[Contemptor Dreadnought]].{{Fn|6}} The [[Thousand Sons]] operated a unique variant of the Castellax class known as the [[Castellax-Achea]].After the [[Horus Heresy]], so many thousands of Castellax Robots were lost that they were not seen again in large numbers.{{Fn|6}}

*Although the [[Kastelan Robot]] for the Adeptus Mechanicus in [[Warhammer 40,000]] has a similar name and design, it is also linked to the [[Horus Heresy]]-era as being an ''"ancient robot built ten thousand years ago"'', with ''"some of them having existed for much longer"''{{Fn|5}}; it is unknown if the different naming convention is intentional or an oversight. For the record, the ''Castellan/Castellax'' denomination preceded{{Fn|1}}{{Fn|2}} the ''Kastelan'' naming convention.{{Fn|4}}