Iron Warriors - Specialist Ranks and Formations: The Trident - The Trident was composed of three exalted Warsmiths of the IVth Legion known as the Triarchs who attended Perturabo as his personal advisors. The Trident existed outside the rest of the IVth Legion's regular command structure. Together the Trident functioned as the soul of the Iron Warriors, supporting their Primarch and steering the IVth Legion's temperament and decisions. Only those Warsmiths who possessed the necessary qualities of strength and charisma were ever allowed to serve at their Primarch's side. The Lord of Iron expected nothing less than the most extreme discipline and loyalty from his Triarchs, but most of all he expected an unbending obedience to the orders he gave. Each blade of the Trident was as solid and unbending as the hand that wielded it.Triarch - An honourary rank reserved only for each of the three exalted Warsmiths who composed the IVth Legion's advisory Trident.Warsmith - The title of Warsmith was an honourary rank held by the senior Astartes Captains who commanded the IVth Legion's Grand Battalions. It was granted for exceptional skill and valour in carrying out the Legion's assaults and gave its bearer command over several of the IVth Legion's companies, which were combined into the larger unit known as a Grand Battalion. After the end of the Horus Heresy, the title would later be the name given to the Chaos Lord who commanded each of the Iron Warriors' myriad warbands of Chaos Space Marines.Honourable - An honourary rank held by the esteemed member of the Iron Warriors that conducted the meetings of the Dodekatheon.Tyrant Siege Terminator Squad - The vanguard of any Iron Warriors siege breakers formation, these warriors were clad in thick Cataphractii Pattern Terminator Armour and deadly carapace-mounted Cyclone Missile Launchers. These implacable warriors were fortress-breakers of unparalleled skill. Recruited from amongst the most battle-hardened Iron Warriors, Tyrant Siege Terminators were expected to brave the most ferocious enemy fire without regard for their own survival. Most often these veteran warriors were found among the ranks of the Stor-Bezashk, the elite siege masters of the IVth Legion, and deployed to other Grand Battalions as need to support siege and assault actions.Iron Havoc Support Squad - The Iron Havoc Support Squads of the IVth Legion were an elite formation who had elevated the tactics of saturating an area or targetting enemy armour with heavy ordinance through sheer weight of fire almost to an art. These warriors were amongst the finest marksman of the Iron Warriors, placing both shell and explosive blast with exacting precision as they advanced alongside the Legion's assault cadres.Iron Circle - Formed in the wake of the attack aboard Perturabo's flagship, the Iron Blood, during the Battle of Phall, the Iron Circle was a self-sustaining unit of implacable killers, devoted servants and incorruptible praetorians all in one. The Iron Circle was composed of six Colossus-class battle robots who served as Primarch Perturabo's Shield Breakers and personal honour guard during the Horus Heresy. Each Battle-Automaton bore the heraldry of a IVth Legion warrior, and their cold machine hearts were loyal in the way it was only possible for an unthinking machine to be.Stor-Bezashk - The Stor-Bezashk were the siege masters of the Iron Warriors Legion, a host of ordnance and heavy artillery specialists who commanded firepower like no other. The Stor-Bezashk were also high explosive ordnance experts and were responsible for crafting the necessary earth-breaching charges used by the Iron Warriors' massive siege-works once the most functional and desirable location for the breach in the enemy's defences had been identified.