A Neutron Laser Projector is one of the most powerful and rare weapons that can be found mounted on a tank of the Imperium, for its power levels are comparable to that possessed by Titan-grade directed energy weapons. Due to the weapon's rarity, the Neutron Laser Projector is usually only mounted on the equally rare Valdor Tank Hunter, which allows the vehicle to fulfil its role as a devastating super-heavy tank hunter. However, during the bygone era of the Horus Heresy, the Cerberus Heavy Tank Destroyer design also featured a twin-linked Neutron Laser Battery as its primary armament.
The neutron energy beam emitted by a Neutron Laser Projector's ray collimator is capable of rupturing enemy armour on a molecular level, often resulting in the target vehicle being vaporised in a massive explosion. Only the most heavily armoured super-heavy tanks and Titan-scale vehicles can hope to survive the forces unleashed by this weapon. Even if the target is not destroyed outright by the intial beam, the neutron energy of the attack will overwhelm and disable the target vehicle's electronics and systems temporarily with a storm of electromagnetic radiation.
Despite the Neutron Laser Projector's sheer power, the weapon suffers from two serious drawbacks. The first is that the Atomantic-Arc Reactors needed to power the weapon are inherently unstable and can cause an apocalyptic explosion if damaged or destroyed. This is most problematic for the Valdor Tank Hunter, where the sheer bulk of the laser and its power source push the limits of the interior space available in the venerable base design of the Macharius Heavy Tank. For the Valdor, this means there is little reactor shielding present to prevent a diastrous rupture of the engine's containment vessels; this often results in either a complete failure of the vehicle's drive systems, or in a massive detonation of the reactor. The second problem is that should the neutron beam fail to transfer its energy discharge entirely into its target, a dangerous feedback can occur to the cannon itself, which can cause damage to the vehicle's hull and electronic systems. On a Valdor Tank Destroyer, the weapon also suffers from a severely limited firing arc, for the projector can only be moved horizontally across a span of 22 degrees. Nevertheless, vehicles mounting the Neutron Laser Projector are greatly valued by those few Imperial Guard regiments fortunate enough to possess them, and are venerated as holy relics by the Adeptus Mechanicus Enginseers who tend to and maintain them.
The Neutron Laser's technology was originally reverse-engineered from wreckage originating from a Dark Age of Technology battlefield, and was recovered at a great cost from the Forbidden World of Deep Hyades VI by Mechanicum Explorators from the Forge World of Galatea. When first presented before the upper echelons of the Mechanicum, some controversy was evident about both the weapon's provenance and safety for dissemination into the armed forces of the Imperium. However, despite the weapon's instabilities, it offered itself as a potential rival weapon to the more common Turbo-Laser weapon systems found on Titans and Shadowsword super-heavy tanks at the time; for it was both more compact in size and possessed an enhanced ability to inflict collateral damage. Shortly before the outbreak of the Horus Heresy in the early 31st Millennium, detachments of vehicles armed with Neutron Laser Projectors were delivered into the service of a number of the Space Marine Legions for comprehensive battlefield testing and trial, although they were soon to turn their own destructive power against the Imperium's own war machines, rather than that of the alien.
Few members of the highest echelons of the Adeptus Mechanicus understand this temperamental technology. As is the norm with many powerful relic technologies from the time before the Horus Heresy, very few Forge Worlds are still able to produce or maintain them, though Mars, Laethe-het and Cryaxus III are three which still possess the capability. Even though the weapon is very powerful, only a scant number of the oldest armoured regiments of the Imperial Guard or units of the Space Marine Chapters have access to vehicles equipped with the Neutron Laser Destroyer amongst their assets in the late 41st Millennium.
- Hadyxis Pattern - A notable variant of the standard Neutron Laser Projector was the Hadyxis Pattern Neutron Beam Laser utilised by Sicaran Venator Tank Destroyers. This was one of the most powerful weapons mounted on any Imperial vehicle of its class. The Hadyxis Pattern Neutron Beam Laser was a more compact and sophisticated variant of the arcane neutron laser array found mounted on the far larger Cerberus Heavy Tank Destroyer. While lacking the sheer damage output of the Cerberus' system, its shorter-focused, densely collimated beam at least dealt with the risks of dangerous feedback that had plagued that weapons system. This advance was only made possible by the Archmagos Jun Hadyxis of Phaeton in the closing decade of the Great Crusade, and along with the life of the savant-genius that created it, the secret of the weapon's construction would be lost in the bitter years of wars to follow.
- Imperial Armour: Apocalypse II, pg. 9
- Imperial Armour Volume Seven - The Siege of Vraks - Part Three, pp. 119-121
- Imperial Armour Volume One - Imperial Guard (Second Edition), pp. 148-151
- The Horus Heresy - Book One: Betrayal, pg. 228
- The Horus Heresy - Book Three: Extermination, pg. 240
- Forge World - Cerberus Heavy Tank Destroyer
- Forge World - Legion Sicaran Venator
- Forge World - Valdor Tank Hunter