maiden tulip
a bonus idea that's related, there could also be projectiles with the same properties as the transformation powder. maybe if they hit the player they turn into some sort of animal as a nod to the rabbit transformation from a link to the past, and a ring that provides immunity to boot.
maiden tulip
now that I think about it, a rod or cane would probably be a better look for the item than a bag of powder because of the pouch already looks like magic powder from older games.
maiden tulip
Transformation Rod (similar to magic powder)