Elemental Marbles

The air represented by white tornadoes…
The water represented by blue water droplets…
The fire represented by orange flames…
The earth represented by green sprouts on brown soils…
These make up the 4 elements of nature!
With these symbols encased in glass-like balls, they make up the elemental marbles.
They shine in the dark, above a glass platform, while also being arranged like sudoku.