Link's Awakening Remake: New Chamber Items?

You already notice how much better the inventory management is in the Link's Awakening remake by how rarely they had to change items during the gamescom footage. But when they did you could briefly spot another new item in the inventory:

Well, there's still the mystery cream item next to the trading item slot, in this case the Pineapple. But this simply might be the new Secret Medicine and there is also something new right between the Secret Seashells and the Sleepy Toadstool.

It looks like a stone slate, but there is a number next to it indicating that this is yet another collectible item. The first thing that comes to mind here are the new chambers that you can get from Dampé as rewards for the Chamber Dungeon, but the item itself looks slightly different:

Here you can clearly see the borders of the chamber with entrances on each end, but the new item in the inventory looks just blank... Plus, there probably wouldn't be much use to keeping track of the number of extra chambers in your inventory, so this might be something else entirely. But maybe it's related, where you can bring these blank chambers to Dampé, so he can turn them into new chambers for you. The coloring of both items is even similar, where they get a little green'ish at the bottom.

Update: According to the official website, you indeed collect additional chambers, which can be earned from both amiibo and other mini-games as well:

Tap compatible amiibo figures to earn more Chambers and [find] additional Chambers throughout the game in updated mini-games, such as the river rapids, trendy game, and fishing.

This could also mean that not all Zelda amiibo will add these "plus effects" to your Chamber Dungeon, some of them might only unlock new chambers. It could also be both, where each Zelda amiibo gives you a new chamber and a plus effect... We'll see, but the Chamber Dungeon certainly seems to be a big focus of the remake.

PS: Note, how the Sleepy Toadstool is there in the inventory together with the Magic Powder. In the original it wasn't possible to have both of these items at once, so there's another minor improvement here. Also, we have to wonder what the slot below the Sleepy Toadstool will be used for. The one between the Secret Seashells and the new slates simply might belong to the Golden Leaves, but the fifth slot is still unclear.

It's also interesting how the Fairy Bottles have seemingly fixed slots within the inventory, instead of simply appearing one after the other. This might even be an indicator for how early you can find the corresponding bottles.