Guys the black one is impossible to get and also i clicked on the view deck source to see if I can discover how to unlock the black but I just placed the black key and unlocked it and when I clicked on the black... Instead of black cube it appeared purple cube

Ключевая вода (key water)

how can i get black?

Hi

How to open the black one

Guys i just realize black one doesnt work cuz there is no possible way to get it