Watch it in action
🫥 How it works
- A Hidden Box starts grey with a ? mark, hiding its real color — until revealed, you cannot tell which color of marble it needs.
- The only way to reveal it is to clear or open a nearby (beside, below, or around it) visible box.
- Once a neighboring box opens, the Hidden Box shows its true color.
- After that it works like a normal colored box that can be filled and cleared.
Pro tip
Treat every Hidden Box as missing information, not just a blocker: clear nearby boxes first to reveal colors and gain control. Do not chase easy matches far away that reveal nothing. Reveal one Hidden Box at a time to avoid overload, and target corner boxes (especially top-left) early — the game loves hiding the color you need in the least convenient place. Keep one safe slot on the belt as buffer before revealing.
