Hidden “?” Cubes and Locked Cubes: How to Play Around Them
2026-08-14 · 4 min read
How hidden cubes work
A hidden cube shows a gray “?” in the tray. Its real color and count are revealed the instant it lands in a waiting slot — which means tapping one is a gamble: you might reveal exactly the color you need, or a color with zero reachable tiles that now squats in a slot.
The safe way to reveal
- Only tap a “?” when you have at least two free slots — one for the reveal, one as insurance.
- Reveal early rather than late: early boards have more reachable colors, so a bad reveal hurts less.
- If a reveal blocks you, Pick Up sends it back to the tray for 50 coins' worth of booster.
- Vacuum can't target hidden cubes — the game asks you to reveal them first.
How locked cubes work
A locked cube (🔒) can't be tapped while another cube sits directly above it in the tray grid. Remove the cube above and the lock releases. Because the tray re-packs itself as cubes leave, a locked cube's cover can change over the course of a level.
Locked cube tactics
- Check what's above a locked cube before you need it — clear its cover during easy stretches.
- Shuffle rerolls tray positions and often uncovers a locked cube for free.
- Spoiler-check the level page: our walkthroughs list every hidden cube's contents and every locked position for that level.
Stuck on a specific level? Open the level walkthrough index for the full written solution and video guide, or play Colony Flow free right on the homepage.