Currently cooking up an idea. Posted this in a discord I am in:

An eon after the Second Sinfall, the end of what is known as the Great Mana War, the world has been changed by the overdose of Mana released into the world: Nature has mutated into bizarre forms, glowing in bright hues and the various races of both sides of the war, the Demon Realm and the former Alliance of Rigstal had to adapt, for the toxic levels of Mana also effect the minds of mortals, long and short lived.

They with the exceptions of a few smaller outpost of nomads or farming communities, retreated into the fortified, and partially hermetically sealed cities, the biggest being Curzosh, the capital of the Demon King. To go out into areas not cleaned from the mana-poisened air they have to wear sealed suits made of the sap of one of the trees evolved after the Second Sinfall and wear gasmasks with filters to prevent themselves from mutating.

With the Sinfall, Magic has also changed, as with the great catastrophe, as the gift of magic had now been turned into a curse, with even the magically gifted and ruling demon race forsaking conventional magic for more earth-like technology (The Cyberpunk element), as well as Mana Alchemy, the art of taking Mana from used filters and turning it into usable potions, aromatics and one-time spells, packaged as either crystals or liquids (Think e.g. a spray bottle that spews frost, fire or changes objects on contact.) However few remain who are born with the ability to cast, though often treated as pariahs, as the mana leaks out of them, necessitating them to wear their Mana Hazard Suits all the time.

Should I post more of it here?