A short while back I had a new Bard subclass I was making, College of the Muse. It might have been lost to the abyss, but the basic idea was that the bard could perform a ritual focused on a specific skill. At the end of the ritual they rolled a d8, and whatever they rolled got added to the chosen skill, along with the appearance of a Muse for that particular skill. I have since thought it might work better as a magic item, with basically the same effect.
Statue of the Muse
Legendary item
Requires attunement
Spend an hour with this statue, complete a ritual and roll 1d8. For the next 24 hours or until the end of a long rest, whichever is shorter, you receive a bonus to a chosen skill equal to your d8 roll. You also receive a Muse in the form of a spirit associated with your chosen skill, who can only be perceived by you, and those who can see into the Etherial plane.
I know, rough description, but this captures the basic idea. Thoughts?
Statue of the Muse
Legendary item
Requires attunement
Spend an hour with this statue, complete a ritual and roll 1d8. For the next 24 hours or until the end of a long rest, whichever is shorter, you receive a bonus to a chosen skill equal to your d8 roll. You also receive a Muse in the form of a spirit associated with your chosen skill, who can only be perceived by you, and those who can see into the Etherial plane.
I know, rough description, but this captures the basic idea. Thoughts?