This magical belt is covered with wereowl feathers. While you wear it, you have advantage on saving throws against being charmed or frightened, and you gain the wereowl's Arcane Weapons, Innate Spellcasting, and Keen Hearing and Smell traits as well as proficiency with Perception and Stealth and darkvision out to 60 feet. You also gain a Dexterity of 17 and an Intelligence of 17 if each score isn't already higher.

Arcane Weapons. Your attacks that use a weapon are magical, and you can use your Intelligence modifier, instead of Strength or Dexterity, for the attack and damage rolls. When you hit with such an attack, the weapon deals an extra 2d4 force damage.

Innate Spellcasting. Your innate spellcasting ability is Intelligence. You can innately cast the following spells:
At will: mage hand, message, minor illusion, prestidigitation, ray of frost
2/day each: detect magic, disguise self, invisibility, magic missile, sleep
1/day: dimension door

Keen Hearing and Smell. You have advantage on Wisdom (Perception) checks that rely on hearing or smell.

Curse. The belt is cursed, a fact that is revealed only when you attune to it. The identify spell is deceived by the curse and falsely reveals the item to be a Belt of Frost Giant Strength. Attuning to the belt curses you until you are targeted by the remove curse spell or similar magic; if the curse is removed, your attunement to the belt also ends. While cursed, you cannot remove the belt, and you refuse to wear any other belt. You also have vulnerability to bludgeoning, piercing, and slashing damage dealt by attacks using silvered weapons. Finally, during nights when the full moon is out, you experience all the effects of the curse of wereowl lycanthropy following the rules described on page 155 of The Impermissicon, including gaining damage immunities, the shapechanger trait (which absorbs this belt into any forms where it doesn't fit), and the change to your alignment. Your DM is free to decide that this places your character under DM control until the sun rises again. During this period, you are able to pass on the curse of lycanthropy just like a true lycanthrope.

Notes: Set: Dexterity Score, Advantage: Saving Throws, Advantage: Perception, Proficiency: Perception, Proficiency: Stealth, Set: Intelligence Score, Buff, Cursed, Belt