Unlimited Magicworks

Doesn't require attunement, just contact with the stone.
You use your action to cast an unrestricted wish spell. By casting the wish spell in this manner, you can use the basic functions of the spell with no consequenses. However, trying to cast a beyond the scope effect will cause stress on the caster's body escalating with the magnitude of the spell. The user takes Xd10 typeless damage depending on the wish and on the DM's discretion. The wish is extremely likely to succeed.