Divine Spirit

"Divine Spirit" is an energy form that generally only naturally appears as the innate life essence of Eradine deities and Minor Spirits. In its basic form, Divine Spirit is the lifeblood of any spectral beings and the source of the Gods' power. This naturally occurring Divine Spirit can be converted to usable energy with sufficient technology. As an industrial energy source for example, it can power specially constructed devices, conjure materials and items out of thin air, or to a certain extent, even manipulate matter itself.
As such, Divine Spirit from Minor Spirits has been used for a long time as an energy source to power machinery, simple tools and even in some cases to spawn valuable resources from nothing.

"Within spectral beings roaming our world, the so-called Minor Spirits, lies an innate essence, a type of energy, that we long learned to harvest; to make use of for our own, to make apparitions work as if moved by the wind, to conjure up objects, and of course, to construct and actuate weaponry and the most formidable tools. Some say our Divines, the Eradine deities, were of the same quality; yet, what logically follows might be one of the most heretic thoughts one single man can invoke."

"The Humble Basics of Spirit Engineering", Second Edition

Obtaining

The conversion of natural sources of Divine Spirit to a usable form of energy is called 'harvesting'. Citizens of Eradin have used various harvesting techniques for decades, and in the case of some Eradine cultures, even for centuries. In the past, Minor Spirits were the only source for Divine Spirit; as they generally were considered non-sentient animal-like spectres, free for harvest.
However, some researchers and scholars have long yearned for a far more powerful source: the Gods themselves. Naturally, the vast majority of people, especially the Eradine Church, have suppressed such notions as blasphemous and outright barbaric. Research into practical applications of using deities as harvest sources carried a severe penalty; as nobody truly wished to upset their benevolent, omnipotent Gods.
However, those who still could not leave this intriguing idea be formed a secret society called the Mantis in the year 2. Secretly researching practical methods to harvest the Gods' Divine Spirit, they endured mostly under strict covers. Eventually, they accomplished a breakthrough, unveiling themselves and taking control of several important locations all over Eradin with the First Upheaval of Mantis. Using their combined knowledge and power, they managed to subdue several Eradine deities and convert them into Divine Harvests.
As of the year 105, these Divine Harvests are the most powerful source of Divine Spirit known and in common application throughout those nations on Eradin sympathetic to the idea. A single Divine Harvest can produce more than a thousandfold of energy output as compared to an entire farmstead of Minor Spirits.

Specifics of Divine Harvesting

In order to convert and contain a God into a Divine Harvest, one has to first subdue the deity. As Eradine deities are physical beings, this proves possible yet difficult, as their godlike powers have to be deflected and defended against. Once the God has been put under control, it shall be placed into a suitable containment: a cell, a room, a cage, a vial. To now convert the captured deity into a Divine Harvest, one has to constantly subject the deity to powerful displays of its own power.

"As a general example for said technique I shall pose a plausible yet fictional God of Battle, if you will. To contain this God of Battle, the harvester needs to subject it to its own prowess; which is, as we have established, the art of battle: violence, bloodshed, pain, if you will. It would be sufficient thus to place the God's physical manifestation, its body if you will, into a cage hung from the ceiling and fastly secured; and continuously pierce it with the strongest weapons and blades known to man, if you will. By this, the harvester robs it of its powers; makes it subservient, able to be subjected to the delicate procedure of harvesting Divine Spirit. If you will, quite possible." - A Mantis scholar's lecture

By application of this method, the deity is unable to rebuild its powers or escape its containment, and thus is able to be harvested for Divine Spirit, usually by electrocution.
If this procedure is interrupted or too weak, the deity can free itself, reigning its wrath over those who dared provoke their own God. After all; they are Gods.

Usage

There are various implements and devices built that accept Divine Spirit as a power source. Industrial machinery that moves on its own if powered, seemingly touched by nothing and nobody. Weapons, charging concentrated charges of Divine Spirit at their enemies. Shrines of conjuration to quickly build entire settlements out of thin air.
However, all of these applications have their cost in Divine Spirit; and the measly output of harvesting Minor Spirits allowed only for minor applications in the past, like allowing plants to grow faster or more fruitful. Practical usages for the enormous amounts of Divine Spirit generated by Divine Harvests however seem to still be in development by the year 105.