Sorry to ask a dumb question here, but uh, how do I play this? I don't know how to open a PDZ file. 😅
Hillslide is a playdate game and pdz is filetype used for playdate games. If you do have a playdate here is a guide for sideloading games https://help.play.date/games/sideloading/
If you don't have a playdate or don't know what it is, it's a small handheld console made by Panic. They do have a simulator where you can play it, but it's mostly made for development. It can be downloaded at https://play.date/dev if you want to try. If you want a refund you would have to contact itch support and they will sort you out