Huge flaw in Bergen Temple Mine

[Papyrus1910]

At the final puzzle in B4 of Bergen Temple Mine, the player is supposed to stand on the key tile and shoot a VRP so that it touches all parts of the puzzle. Some certain parts of the puzzle was protected with key barrier. However, if the player accidentally shoots a key barrier, their key will be used up, leaving them with no other option to progress further. Leaving the room doesn't reset it as well as the key count. Was this intentional, and players need to find hidden keys, or was this a design flaw?

[veetosmuro]

This doesn't sound like a bug to me? All you need to do is collect all the keys and use them to open the barriers. You can't "accidentally" use your key on a wrong barrier because it's intended that you use them all to open all barriers

[lachsen]

I don't see any way how you can use up all keys in that area to be stuck. You need one key to enter the room of the last puzzle + afair 3 additional keys to unlock the barriers inside the room. There are 4 keys in total in that floor so there is no way to use up your keys in a way that makes you stuck.

Note: you don't need a key to actually solve the bounce puzzle in that room.

[Papyrus1910]

Oh, I'm terribly sorry. I didn't realize a key wasn't required to solve the puzzle. Besides, there were several hidden passages that I haven't discovered yet. My bad.

[pyrocorvid]

There's 4 of them, one to get into the puzzle room and 3 to unlock the puzzle. You can find them in these rooms: https://imgur.com/a/5XgMFQJ

[wervyn]

Have a video walkthrough! Starting from B4: https://www.youtube.com/watch?v=0jJfLjg8aYc&t=3218s

There are specific breakouts for timestamps on the dungeon in the description, so if you just need to see which rooms the key chests are in and how to solve them look at that.