This work was designed as a Christmas present for 2023.
This is a composite of "Dice" (P-9), "Top Box" (M-5), and "New Secret Box" (M-38).
The shape is "Dice", the structure is "New Secret Box", and the mechanism is "Top Box".
However, the mechanism has three levels and is quite complicated.
All six boards move, but the trick is only in three boards, and the movement of the other three boards is fake.