Arcturus descended from the heavens and is currently in the form of a gauntlet. A druid attuned to Arcturus gains a +2 bonus to their constitution score, a +1 bonus to spell attack rolls, advantage on strength checks while in animal form. They can also cast spells while in the form of ursine animals.
In addition to this, they also gain the following.
Blessing of the Bear Star. You cast a celestial aura around you with a 30 foot radius. Allies inside that radius do an extra 1d4 radiant damage. Once you use this ability, you cannot use it again until the next day.
Nature's Guardian. Once weekly, you can become a ward of Nature itself and cast Nature's Guardian.
Wrath of the Bear Star. You can manifest the rage of the Star Bear in yourself, push beyond the limits of your body, and transform into a Dire Bear. This transformation can last for upto 10 minutes, and can end earlier if you choose. When transforming back, make a Constitution check. On a roll of 10 or higher, you return to your normal form as you were before the transformation. On a roll of 5 - 9, you return to your original form with a single hit point. On a roll of less than 5, you return to your original form and immediately drop unconscious.
Notes: Bonus: Constitution Score, Bonus: Spell Attacks, Requires attuned by a druid.