Radium Weapons, also known as Rad Weapons, are deadly and highly dangerous personal weapons that are used exclusively by the forces of the Skitarii Legions of the Adeptus Mechanicus. Many weapons wielded by the Skitarii are so deadly to the wielder they're widely condemned by the rest of the Imperium. Their baroque beauty belies a singularly vile function -- not only to strike, but to render the battlefield as deadly as the rad-wastes of Mars.
As dangerous as they are to their wielders, Radium Weapons are far more deadly to the enemy. Armour may repel the solid rounds, but only the most heavily-reinforced battle-plate can protect the target from the baleful energy given off by the hyper-irradiated bullets. As more and more shots are fired, the area becomes increasingly saturated with radiation until a localised rad-storm occurs, striking down the enemy with radiation sickness and leaving the ground beneath their feet saturated and lifeless.
Radium Weapons are so volatile that they eventually kill their wielders. The war plate worn by the Skitarii Vanguard, combined with their rad-leeching robes and augmetic limbs, goes some way to protecting them from the harmful feedback generated by these weapons, though inevitably some still seeps through. The Vanguard welcome this, for they are the Omnissiah's holy warriors and even the lethal touch of radiation is a sign of His blessing. Over time their bodies become so saturated with radiation they become weapons themselves, their mere presence enough to leave an enemy soldier reeling with nausea and a hacking cough laced with bloody phlegm. Death follows soon after.
Known Radium Weapons
The Radium Carbine is a rapid-firing weapon capable of a punishing rate of fire, and serves as the main armament of the Skitarii Vanguard.
- Codex Adeptus Mechanicus - Skitarii (7th Edition), pg. 74