Ripheus23

The Forge: magic system involving being magically tied to a specific structure called the Forge, which contains artifacts, the Instruments of the Forge, that can be invoked at a distance by people who are Forge-tied. These are usually large vaults of things like hammers, glowing rings, some swords, etc. Depending on how many people channel an object at once, it can start to resonate more and more violently inside its vault in the Forge, until arcane glyphs/runes manifest around it and close off its channel. [The rings are known to glow reliably even when being drawn on by hundreds of thousands of people per ring at a time; and there are millions of these rings in the vaults.] Forgeswords have some kind of fearsome or inauspicious powers, though IDK what yet. I don't want them to be Shardblade-analogs, to be sure

Anyway, the Messiah of Despite was sealed by the Messiah of Daylight ages ago, by allowing the Servant-avatar to perpetrate two of the incarnations of the Final Sins upon his person. It was ages later when the Princess-goddess, Lavaliere Arestroissa, opened the vaults and the Anvilheart of the Forge to the masses of her and all other lands. When the Messiah of Despite arises again, it is to use the flaw in the seal to fulfill the "prophecy of free will": when the Creatrix was destroyed by the Despite-god during the foundations of the world, She imparted a possibility into the flux of history: that at unknown intervals, the forces of the Final Sins would have the power to end creation entire, and it would always be for the people of the world at those times, in those days, to defy evil unto salvation.