Mana Crystals

Mana crystals. The crimson tools that made the Empire of the Sun what it is today.
The size of the crystal depends on the amount of power stored within it. From small crystals that can fit inside a neckless to the 7 meters tall giant inside the Demonfall Cathedral.
In their raw form they are coarse and uneven like any other crystal. Their nature is that of magical energy given solid form, which makes them extremely hard and impossible to shape with phisycal tools, but someone capable of magic manipulation can easily reshape the crystal in a more practical form.
Usually, when a crystal is created it is shaped and embedded inside a tool, until its stored magic is used up. After this the old crystal is removed and a new one is embedded in the tool.
Those tools can be rings, necklesses, shields, staffs or any other preference of the user. The only use of the tool is as a more easy and secure transport and use of the crystal.
Some members of the priesthood even prefer to carry their mana crystals by hand, whithout embedding them in a tool.

Utility

The crystals act as a source of stored magical power. Anyone who can use magic can take the sored power and empower his spells by increasing their raw power, scale or duration. The stored magical power is limited and the amount that can be drained at once depends on the user's personal skill.

Manufacturing

The ritual for creating the crystals is the Empire's greatest secret, known only to the members of the Exarch Council. But over the centuries long exisance of the Empire, rumors got out and became myths and legends. The legends tell of ritual that use the magical energies stored in the soul of living beings. That beings like the godkin and their gods have greater amounts of magic in their souls than humans. That this is the reason for the constant invasions by the Empire and the extermination policy towards godkin races.

Access & Availability

The power given by the mana crystals is one of the pillars of the Empire's power. Because of this, their production and distribution is strictly regulated.
The only people who have the knowledge on how to create the crystals are the members of the Exarch Council and the only one who can make decisions on distributing them is the High Exarch, the other members of the Council can only make suggestions and recomendations.
To lower the risk of revolts and rebelions, the Church of the Sun keeps the crystals only between their members and gives them only to priests and inquisitors which have demonstrated their loyalty to the High Exarch and the Church.
Even the highest ranking lords and commanders are forbidden from carrying and using the crystals. Anyone, who is caught with more crystals than he is allowed, is severely punished, even by execution.

Discovery

The legends say that in the founding days of the Empire, the Sun God himself apeared to Augustine, the founding high exarch within a dream. And in this dream he gave him not only his blessing, but the knowledge on how to create the mana crystals.