Stormcloud: Once per day you can use an action to cast Call Lightning (4th level) using this ring.

At Home in the storm: Any creature attuned to this ring gains a +1 bonus to their Constitution score. If the attuned creature is a Tempest Cleric they also receive a +1 bonus to their Wisdom score. If they are a Storm Sorcerer they receive a +1 to their Charisma score.

Only one of these last two bonuses apply in the case of multiclassing, it will always be the class the creature had first or has the most levels. If this is unclear, choose the highest score. If it's an even score, the creature chooses one of the two options.

Notes: Bonus: Constitution Score, Requires attunement by a Cleric, Druid, Sorcerer, or Wizard