Eldritch Mechanism

'Eldritch mechanisms' is a somewhat old-fashioned turn for what modern artificers term Voidsource Arcanotech. Unlike Magic items, arcanotech uses arcane science to derive its effects and can, in theory, be mass produced. Aiaosian arcanotech is very limited in the latter regard, and some have turned to Void sources to try to overcome those limits.
Most of the known mechanisms are weapons or armor of the Outerfolk, used in the Colossus War. This includes ilithid Voidsuits - fashioned by alchemically treating discarded nautiloid hull plates to temporarily soften them - and energy weapons. All of these use Voidspar-based power packs and are harmful to any Aiaosian trying to use them.
The destructive power of bleakstone is employed in The Creation of jadefire, a form of gunpowder that burns with a green-black flame. Voidlock firearms - powered by jadefire, ignited using a Voidspar striker - are significantly more powerful than those using alchemical black powder or even arcane smokepowder, but are prone to failure and produce especially noxious fumes.
One of the most feared relies of the ancient war, Hadar charges use a mix of jadefire and hadarite to produce a flame that consumes almost any matter, living or inanimate, in a wash of black flames.
Rare and complex, the Foulheart is a mechanical heart designed and built from xeno- and paramaterials, mixed with Imperishable Substances, and designed to pump foul ichor through the bodies of Void constructs. Unholy fusions of living flesh with Eldritch Mechanisms, these beings are terrible in their power and invariably wracked with pain. They are creatures of pure rage and destruction, never made for any other purpose, or at least, never successfully made to any other purpose.
Also categorised as Eldritch Mechanisms, regardless of their actual form, are Relics of the Colossi themselves. Bound in alien magic, defiant of all natural and arcane law, these foul remnants of the Colossus War cause nausea and disorientation by their very presence.