Watch it in action
🕵️ How it works
- This Mystery Box is a grey ? box at the bottom hiding the real color of a collection box until it is revealed.
- It reveals its color only after the box directly above it is cleared — the stacked top box is the lock.
- The reveal sequence: find the grey ? box, check the box above it, fill and clear that top box, then the Mystery Box turns from grey ? into its true color.
- Hard levels place several Mystery Boxes at the bottom at once, creating a chain: you cannot see every target, so you clear visible boxes and adapt.
Pro tip
Clear visible boxes for guaranteed progress, and pick the stack with the easiest box above a Mystery Box to reveal one color at a time for control. Stop dropping colors with no target, and save flexible colors that appear in multiple upper boxes for after a reveal. If the revealed color is already rolling on the belt, pause half a second and let the marbles travel before dropping the next matching set — players lose this by over-tapping.
