Thrymmian Crystals

The Hollows

Magical disease
Born from the use of Thrymmian Crystals, this sickness removes a person's magic's affinity to the 'being'. In short. the weave does not recognize you as a separate entity, and as such, your force of personality and health begins to wain. This can be recognized by a general lack of drive in a person, as well as white-veined corruption (mostly coalesced around the limb that was used for casting).
On your first "Hollows" advance (from this point - "fail"), begin tracking their number. Once three have accumulated, your character is afflicted with the "Hollows" (see below) and any conventional means of healing them are unavailable. Prolonged periods of rest, as well as the "Greater Restoration" spell (not from a Thrymmian Crystal) can remove a fail.
When afflicted with the "Hollows", every 1d3+1 (rolled in secret) days, the DM will have you make a DC 13 Constitution saving throw. Count your successes. On a fail, you lose one point from your Charisma and Constitution scores, down to a minimum of 3. Once one of these attributes' scores drops to 3, the character becomes nothing more than a thrall. At this point, if the afflicted character is a PC, the DM takes over control (unless the character is, at any point, healed). Alternatively, 7 successes render a character cured from the "Hollows". Their Charisma and Constitution scores begin to replenish at the same rate of one every 1d3+1 days.
Continued use of Crystals after recovery still yields many complications, although far less threatening - at this point, they are mainly flavored, as the user has become what the Thrymmians consider to be a proper sorcerer. The worst case scenario is becoming afflicted once more.

Spells:

• Cantrips: Eldritch Blast, Thaumaturgy, Spare the Dying, Booming Blade
• 1st Level: Chaos Bolt, Magnify Gravity, Cure Wounds, Detect Magic, Thunderous Smite, Charm Person
• 2nd Level: Ray of Enfeeblement, Misty Step, See Invisibility, Lesser Restoration, Invisibility
• 3rd Level: Dispel Magic, Pulse Wave, Slow, Life Transference
• 4th Level: Dimension Door, Death Ward, Gravity Sinkhole
• 5th Level: Destructive Wave, Greater Restoration, Telekinesis
• 6th Level: Gravity Fissure, True Seeing, Heal

Rules:

• It takes an action to harness the power of a Thrymmian Crystal. As part of that same action, you can cast a spell from the list. Doing so expends the Crystal's spell slot.
• You can choose to hold the effect off for up to 1 minute. Until then, you have a single Cystal spell slot in the "aether", which can be used either for spell slot recovery or to cast an appropriate spell from the list. You can maintain one such "aether" spell slot at a time.
• You can cast any lower level spell from the list if you so wish. Additionally, if possible, you can upcast the spell (ex. 3rd level Cure Wounds).

Common

1d20	Common (25 GP) DC 11, +3 to hit
1	Same as above, but the caster’s “Hollows” affliction advances by 1.
2-3	You are able to cast the equivalent of a cantrip
4-17	You are able to cast/recover a 1st level spell (chosen from the list)
18-19	You are able to cast/recover a 2nd level spell (chosen from the list)
20	You are able to cast/recover a 2nd level spell (chosen from the list) If you choose to cast, you can apply any one of the Sorcerer's Metamagic options to the spell. You must make a DC 12 Constitution saving throw, on a fail the caster’s “Hollows” advance by 1.

Uncommon

d20	Uncommon (75 GP) DC 13, +5 to hit
1	Same as above, but the caster’s “Hollows” affliction advances by 1.
2-3	You are able to cast/recover a 1st level spell (chosen from the list)
4-17	You are able to cast/recover a 2nd level spell (chosen from the list)
18-19	You are able to cast/recover a 3rd level spell (chosen from the list)
20	You are able to cast/recover a 3rd level spell (chosen from the list) If you choose to cast, you can apply any one of the Sorcerer's Metamagic options to the spell. You must make a DC 14 Constitution saving throw, on a fail the caster’s “Hollows” advance by 1.

Rare

d20	Rare (150 GP) DC 15, +7 to hit
1	Same as above, but the caster’s “Hollows” affliction advances by 1.
2-3	You are able to cast/recover a 2nd level spell (chosen from the list)
4-17	You are able to cast/recover a 3rd level spell (chosen from the list)
18-19	You are able to cast/recover a 4th level spell (chosen from the list)
20	You are able to cast/recover a 4th level spell (chosen from the list) If you choose to cast, you can apply any one of the Sorcerer's Metamagic options to the spell. You must make a DC 16 Constitution saving throw, on a fail the caster’s “Hollows” advance by 1.

Very Rare

d20	Very Rare (500 GP) DC 17, +9 to hit
1	Same as above, but the caster’s “Hollows” affliction advances by 1.
2-3	You are able to cast/recover a 3rd level spell (chosen from the list)
4-17	You are able to cast/recover a 4th level spell (chosen from the list)
18-19	You are able to cast/recover a 5th level spell (chosen from the list)
20	You are able to cast/recover a 5th level spell (chosen from the list) If you choose to cast, you can apply any one of the Sorcerer's Metamagic options to the spell. You must make a DC 18 Constitution saving throw, on a fail the caster’s “Hollows” advance by 1.

Legendary

d20	Legendary (2000 GP) DC 19, +11 to hit
1	Same as above, but the caster’s “Hollows” affliction advances by 1.
2-3	You are able to cast/recover a 4th level spell (chosen from the list)
4-17	You are able to cast/recover a 5th level spell (chosen from the list)
18-19	You are able to cast/recover a 6th level spell (chosen from the list)
20	You are able to cast/recover a 6th level spell (chosen from the list) If you choose to cast, you can apply any one of the Sorcerer's Metamagic options to the spell. You must make a DC 20 Constitution saving throw, on a fail the caster’s “Hollows” advance by 1.