Genesis 「True Dweomer」

9th-level Conjuration (Druid, Sorcerer, Wizard)

Casting Time: 24 hours or Circle Spell option
Range: 180 feet
Components: V, S, M (a flawless crystalline sphere worth at least 50,000 gp, which the spell consumes)
Duration: 3 days

You spend 24 hours tracing magical pathways and deciphering the fundamental fabric of reality on the Ethereal Plane to birth a permanent pocket dimension—a new demiplane. Upon completion of the casting, a localized density fluctuation manifests, expanding at a rate of 1 foot in radius per day until it reaches an initial maximum radius of 180 feet.

When casting this spell you must target a point you can see, while physically on the Ethereal Plane, and within range. A permanent pocket dimension—a new demiplane—erupts from that point, expanding outward at a rate of 1 foot in radius per day until it reaches an initial maximum radius of 180 feet.

You exercise absolute control over the initial environmental factors of this realm, determining its atmosphere, temperature, water availability, and general terrain layout (such as floating earthmotes or flat plains). It cannot inherently manifest complex structures or sapient life upon creation. If this spell is cast within a demiplane you have already created using Genesis, its boundaries permanently expand by an additional 180 feet in radius.

Additionally, you must succeed on a DC 55 Intelligence (Arcana) check to decipher the foundational science of high-magic spellcraft and anchor the new reality. On a failure, you suffer backlash as the spell automatically fails and you take 99 (18d10) psychic damage, the demiplane dissolves, and the material components are wasted. After this spell is cast, you gain 1 level of Exhaustion. This effect ignores resistance and immunity. While you have Exhaustion levels gained from this spell, finishing a Long Rest neither restores lost Hit Points nor reduces your Exhaustion level.

Casting this spell on the same spot in the ethereal plane for seven days makes this effect permanent.

True Dweomer. Magic of high power automatically fails the very first time you cast this type of spells, requiring you to expend twice the amount of time and resources to effectively complete this magic of high power at least once. In doing so, and successfully casting a true dweomer spell, you attract instant cosmic scrutiny. The severe metaphysical friction of shaping this forbidden magic weakens your form. After casting this spell, each time you cast a spell until you finish a Long Rest, you take 1d10 necrotic damage per level of that spell. This damage ignores resistance and immunity. Furthermore, your Constitution score becomes 3 for 2d4 days while simultaneously your Intelligence score becomes 3 for one month. For each day you spend resting and doing nothing more than light activity, your remaining recovery time for your Constitution score decreases by 2 days. Finally, there is a 33 percent chance that you are unable to cast Genesis ever again.

Casting as a Circle Spell. Casting this as a Circle spell requires a minimum of two secondary casters. If the spell is cast as a Circle spell, its casting time is reduced to 8 hours. Also, every caster in the circle gains 1 level of Exhaustion per assistant participating (to a maximum of 4 levels from this rite).

When you cast the spell, you perform one of three rites of your choice. Rites are cumulative, with each option incorporating the previous effects:

• 2–5 Casters Rite: The initial radius of the demiplane increases to 360 feet, and its expansion rate increases to 10 feet per day.
• 6–8 Casters Rite: The initial radius increases to 1 mile, and you can imbue the demiplane with one minor elemental trait (e.g., permanently illuminated, continuous light rainfall, or mild gravity).
• 9+ Casters Rite: The initial radius increases to 10 miles, and you can manipulate time inside the demiplane, making time pass up to twice as fast or twice as slow relative to the Material Plane.

Each secondary caster must expend a 7+ spell slot when the spell is cast, otherwise, it automatically fails.