Hat of True Frog
A small green leather skullcap, with two bulbous white eyes atop it and a chin strap whose clasp is reminiscent of a three-toed frog’s feet.
Any living creature wearing this hat on their head must make a DC 18 wisdom saving throw or be permanently transformed into a frog, with all the statistics and abilities thereof. The hat fits snugly upon the frog’s head; if the clasp is secured, the frog can move freely without removing the hat. If the clasp is not secured, the frog can make a DC 15 Strength (Acrobatics) check to see if it can dislodge the hat.
The effect is ended by removing the hat, being knocked unconscious or killed, or with the effects of a wish spell.
Once the effect is ended, the creature is immune to its effects for 24 hours.