I'm going to assume your talking this in the aspect of knowing the gods
See there are ways of divination. Tarot deck is one of them but you simply can not empowers it as a black mirror as
You need something that is permeable /pardon my English I'm not native. In the sense that.
You gotta take something that you can see through. I.e water in a bowl like the yellow in the glasses picture or true (for beginners) reflective like a mirror\chrome not just something clean and should be empowered
Meaning u cant do the same thing for a tarot deck.
But a black mirror is like live production while tarot is like finishing a level in a game then getting your answa .
See the tarot gets easier because their no harder levels maybe 4 3 hard levels but they are all same
But black mirror is like glimps. Then 3 second view. Then 1 second color view / till you become better. And if you're not carefull can evolve into an 8 Dimension view of everything, seeing rain. Hearing rain, rotate ional feel movement - Basically u immarsed
So there's a learning curve with that that gets get steeper as it go s
Btw also ANY bottle of water is good no need to be expensive or weird looking into a bowl of water clear bottle water
And a bowl of water can be infected if open. Remember to store it in a dark place after u done or wrap it entirely in silk cloth