This magical belt is covered with wereturtle scales. While you wear it, you have advantage on saving throws against being charmed or frightened, and you gain the wereturtle's Hold Breath and Innate Spellcasting traits as well as proficiency with Perception and a swimming speed of 25 feet. You also gain a Constitution of 15 and a Wisdom of 15 if each score isn't already higher, but your Dexterity is reduced by 2 and your walking speed is reduced by 5 feet.

Hold Breath. You can hold your breath for 1 hour.

Innate Spellcasting. Your innate spellcasting ability is Wisdom. You can innately cast the following spells, requiring no material components:
At will: druidcraft, poison spray, resistance
2/day each: create or destroy water, cure wounds, entangle, pass without trace, spike growth

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 wereturtle 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: Constitution Score, Advantage: Saving Throws, Proficiency: Perception, Set: Wisdom Score, Bonus: Speed (Walking), Bonus: Dexterity Score, Set: Speed (Swimming), Buff, Cursed, Belt