Ring of Obscuring

This band of iron resembles a skull and is
cold to the touch. It has 3 charges and regains 1d3 expended charges daily at dawn.
As an action while wearing the ring, you can expend 1 of its charges to cast the fog cloud spell from it, with the following changes: the cloud is centered on you when it first appears, and the spell lasts for 1 minute (no concentration required).