This ticks all the boxes! I am surprised how much it feels like a full game. It reminds me a bit of Bards Tale III with all the different realms you can visit. Combat and progression were fun, balanced, and understandable. I'd love to see it developed further!
The issue I had with the inventory was that it was hard to equip items as they did not seem to appear in your inventory after I picked them up. However, if you unequip an item, it goes to the bottom of your list and you can cycle through all the items that way. It's a bit wonky, but that's a game jam, right? Also, if you already have a certain item, just don't pick any more up, as they will prevent other items from showing.