Partial Answer
If we solve the cube with the writing on it we get:
This suggest that each section is a letter in the alphabet: (I'll update the picture in a second)
This is why Y and Z cards are missing, there are only 24 squares
Partial Answer
If we solve the cube with the writing on it we get:
This suggest that each section is a letter in the alphabet: (I'll update the picture in a second)
This is why Y and Z cards are missing, there are only 24 squares