Soul Sphere

This perfectly spherical orb emits soft blue light and has strange markings in an uknown language inscribed upon it. It contains the soul of a long dead creature, that can grant the wielder greater magic.

While holding this sphere, you gain a bonus to spell attack rolls and to the saving throw DC of your spells. This bonus is equal to half your proficiency bonus (rounded down).

In addition, you can regain one spell slot as an action while holding the sphere. The spell slot's level must be equal to or less than half of your proficiency bonus (rounded down). You can't use this property again until you finish a long rest.

You may perform a 10 minute ritual while holding this sphere to regain all your 5th level and lower expended spell slots. Doing this consumes the soul contained within the orb, after which it becomes a normal item and loses all its properties.