"We could face off Imperial energy rifles in the Flight, those Selenic abominations during the war, and the bugs that made up the Helleonic Confederacy, all without flinching. And yet of everything I have ever fought, it is the arc weapons' wrath that I dread facing again..."
An arc weapon is a classification of hyper-advanced energy weapon used by the soldiering caste of the Khazard'Vaari dynasties. Resembling a staff at first glance, it is common for them to appear with deadly blades, usually reminiscent of an axe, slung underneath in case the warrior wielding it must fight in close-quarters.
All arc weapons possess a micro-singularity built into them, from which the weapon draws massive amounts of electrical power to turn on any unfortunate foe in its wielder's path. When the user wishes to fire it, that power is diverted to the focusing array at the front of the 'barrel' and released as a blast of superheated, green lightning. Approaching the temperature at the surface of a star, this lightning will melt even powered armour in microseconds, still less flesh, and electrocute anyone who survives the strike with such ferocity that they are usually placed into immediate shock (pun intended) from the agonising pain, rendering them helpless against a second, better-aimed kill shot.
There are several known types of arc weapon used by Khazard'Vaari warriors, and they bear the same general design across the board. The most common is designated the 'arc-reaper', and is the nearest equivalent to an assault rifle. Most arc-reapers bear a blade similar to a greataxe slung beneath the barrel, themselves being shaped like battleaxes for ease of use in close-quarters combat.
Another, heavier arc weapon is given the designation of 'arc-ravager'. Resembling a halberd, they produce a much more powerful electrical blast for defeating hard-targets. Arc-ravagers also comes with a function that allows them to fire a highly-volatile bolt of ball-lightning, the projectile violently exploding on contact with solid matter and leaving a lingering electrical cloud. Arc-ravagers are a common sight among a phaeron's Royal Guards, usually constructed from the same adamantite hyperalloy as their bodies, but can be found in the hands of lesser troops on occasion.
Other arc-weapons range from the 'arc-slicer', a small, hand axe-sized weapon comparable to a pistol for commanders or shieldbearers to use, all the way up to the 'arc-eraser', a powerful autocannon-grade weapon typically seen on Scyther gunships – with heavier Khazard'Vaari war machines arming themselves with devastatingly-powerful mag-artillery pieces.
Although it is theoretically possible for a human, a Sidh or a Skargh to wield a Khazard'Vaari arc-weapon, it would be very unwieldy and difficult to aim properly. A baseline human would struggle to pick it up, an arc-reaper weighing in excess of 15kg, let alone aim it. A Sidh could easily lift it with powered armour, but would struggle to fit the massive fingers of his gauntlet in the trigger-loop, relegating the weapon's use to melee only. That is not to say arc-weapons tech is completely out of human reach: the Mecharussians would reverse-engineer several prototype handheld arc-weapons ready for testing by 2172 AC, and the World Eater hyperdreadnought uses a derivative of arc technology to power its singularity laser.