The Arcus Launcher is a rotary missile launching system that was once use by the Space Marine Legions on their Sicaran Arcus Strike Tanks during the Great Crusade and the Horus Heresy in the late 30th and early 31st Millennia. The Sicaran Battle Tank was an Imperial main battle tank and one of the most advanced armoured vehicles ever used by the Imperium, and the Arcus variant was no different. The Arcus Strike Tank was originally part of a program once initiated by the Primarch of the Ultramarines Legion, Roboute Guilliman, seeking to grant a Legion strike force access to highly specialised weapon systems without the need to employ numerous vehicles for each role. The Sicaran hull was chosen to mount the newly developed Arcus Launcher, which was capable of deploying with a wide range of warheads, each crafted to fulfil a distinct tactical niche during combat. The Arcus was intended to become the cornerstone of a new tactical doctrine the Master of Ultramar had begun to formulate, allowing small Legiones Astartes forces to operate without extensive support and in smaller numbers than during the Great Crusade.
Despite production of the Arcus being limited to a few prototype vehicles at the onset of the Horus Heresy, and the doctrinal issues that kept it out of production on most major Forge Worlds, a number of Legion homeworlds produced small numbers of this variant. Of particular note is the inclusion of the Neutron-flux Warheads, a Terran development dating back to the years prior to the Emperor's alliance with Mars. This weapon saturated the silica stratum of the Cybernetica Cortex employed by Mechanicum Automata with xenon, causing terminal cascade failures in those systems. The continued production of these weapons is believed to be the cause of the Mechanicum's refusal to sanction the Sicaran Arcus Pattern, and its inevitable downfall.
The Arcus Launcher was capable of being outfitted with a variety of warheads for its missiles, each crafted to fulfil a distinct tactical niche during combat. The following are all known warhead types usable by the Arcus Launcher.
The standard warhead type for the Arcus Launcher, Arcus Warheads were a cluster munition that upon detonation would send many smaller explosive devices over a large area. These warheads were particularly effective against enemy infantry and light vehicles.
The Skyspear Warhead is an anti-air warhead that includes sophisticated tracking instruments that allow the warhead to steer the missile towards its target, effectively turning the Arcus into a surface-to-air platform. These warheads are effective against enemy aircraft.
Pyrax Warheads are heavy explosive-type munitions that are used in the removal of cover and heavy terrain. These warheads are effective at eliminating cover used by the enemy, along with the destruction of fortifications and terrain obstacles.
A Terran-made warhead dating back to the years prior to the Emperor's alliance with Mars, the Neutron-flux Warhead saturates the silica stratum of the Cybernetica Cortex employed by Mechanicum Automata with xenon, causing terminal cascade failures in these systems. The continued production of these weapons is believed to be the cause of the Mechanicum's refusal to sanction the Sicaran Arcus pattern vehicle for general use by the Imperium, and the switch to the use of the Rotary Missile Launcher on Relic Sicaran Arcus tanks still held in Space Marine armouries in the 41st Millennium.
- Forge World Webstore - Legion Sicaran Arcus Strike Tank
- Forge World Webstore - Relic Sicaran Arcus Experimental Rules (PDF)
- Forge World Webstore - Legion Sicaran Arcus Experimental Rules (PDF)