A Castellan is a specialist officer rank that is unique to the Black Templars Space Marine Chapter, and is the equivalent of a Space Marine Captain of a Codex Astartes-compliant Chapter. A Castellan is responsible for leading an entire Fighting Company of the Chapter on the field of battle during the numerous ongoing Crusades conducted by the Black Templars. Larger Black Templars Crusades often comprise a number of the Chapter's Fighting Companies, each led by a Sword Brethren (Veteran) raised to the rank of Castellan. Only those Sword Brethren who have proven themselves as devotional warriors and inspirational leaders may rise to this esteemed rank. These hardened Veterans have earned their ascension to command rank through their bloody and zealous dedication to the Chapter's cause. As masters of the battlefield, Castellans are able to read its ebb and flow, and adjust their tactical formations accordingly. Leading from the front by example, a Castellan's Astartes know what it is to be a Black Templar and a dedicated warrior of Sigismund and the Emperor, and from his leadership they learn the trade of battle and the craft of death.
- Castellan Adlar - Castellan Adlar commanded Fighting Company Adlar of the Solemnus Crusade during the Third War for Armageddon. Fighting Company Adlar deployed to the surface of Armageddon to stall the Ork invaders and search for the Red Scar Ork Tribe that had destroyed the Solemnus Chapter Keep. Castellan Adlar fell during the assault on the Blood Scar Tribe's Gargant factory, pinned by a crashed Ork Trukk. Brother Adlar used his Thunder Hammer to detonate the munitions stockpile of the Kannon emplacement where he was trapped and dying, and took every Greenskin in the vicinity with him.
- Castellan Draco - Draco first rose to prominence as part of Marshal Ludoldus's Sword Brethren during the bitter Vinculus Crusade in which he fought a Renegade Inquisitor named Lord Vinculus. Draco was badly wounded after the battle and his body was reconstructed with bionics. He was awarded the rank of Castellan and was given a relic suit of the Chapter's finest Power Armor for his valour. Draco's contributions were further recognised when he was presented with the former Inquisitor's blade as a mark of gratitude from the Ordo Hereticus.
- Power Armour
- Terminator Armour (Optional)
- Bolt Pistol (Optional)
- Crusader Seals - Crusader Seals are waxen or metallic tokens with vows of piety and Chapter blessings inscribed on hanging strips of parchment that are bestowed upon Black Templars Astartes of proven zeal and courage.
- Storm Bolter (Optional for Castellans in Terminator Armour)
- Close Combat Weapon (Choice of Power Sword, Chainsword, Lightning Claws, Thunder Hammer, Power Fist; if chosen weapon is one-handed, a Storm Shield may also be used)
- Frag Grenades or Krak Grenades
- Codex: Black Templars (4th Edition), pg. 15
- Deathwatch: Core Rulebook (RPG), pp. 38-39