Mossy Stack

What you do

Mossy Stack is an endless one-button stacking game in a woodland. A moss-topped log swings back and forth above your tower, and only the part that lands on the tower stays, so every sloppy drop leaves a narrower log for the next one, while dead-center Perfects keep your width and streaks of them grow it back. The camera rises with the tower, from the forest floor past an owl on its branch, through flocks of birds and clouds, into a golden sunset and finally a starry night. The higher you go, the faster the logs swing, and one drop that misses the tower ends the run. Your best height, best streak, and best score are saved in this browser.

• A dashed best-height line during play and a zoomed-out view of the whole tower when the run ends.

How to play

1. Press Play. A mossy log swings back and forth above your tower.
2. Tap anywhere, click, or press Space or Enter to drop it. It falls straight down where it is.
3. Only the part over the tower stays; the overhang is trimmed off, so the next log is narrower. Dotted guides above the tower mark its edges.
4. Drop within a few units of dead center for a Perfect: the log snaps to center and keeps its full width. Each landing scores 10 points, and Perfects add a bonus that grows with your streak (20, 30, and so on, up to 100).
5. From the third Perfect in a row, every Perfect grows the log a little wider again, up to the width of the base.
6. The logs swing faster as the tower grows. From height 9 some logs are quick (they trail speed lines); from height 12 logs come from either side; from height 25 some logs sway like a pendulum, slow at the ends and fast over the tower.
7. A red mushroom cap comes along when the tower has thinned: it is wider than the tower, so landing it wins back width. A log with a bird nest pays 50 points, or 150 if you land it dead center.
8. Milestones such as Fern Ledge (10), Owl Branch (20) and Moonrise (100) each add 100 points. One drop that misses the tower entirely ends the run.

Controls

• Touch: tap anywhere on the forest.
• Mouse: click anywhere on the forest.
• Keyboard: Space or Enter. The forest takes focus when a run starts; holding a key drops only once.
• Toolbar: pause, restart, sound, help, and fullscreen. The results screen only continues with its Play again and Title buttons.

Tips worth knowing

• Tap a moment before the log lines up. The drop happens the instant you press, so anticipate it rather than reacting.
• Watch the top log of the tower, not the wider logs below it. The dotted guides mark its edges.
• You can let a log pass and drop it on the next swing. There is no timer.
• Protect your streak: three Perfects in a row are worth more than a rushed drop, because they start regrowing width.
• Swaying logs move fastest over the middle. Start your tap a touch earlier than for a gliding log.

Accessibility

• One button: tap anywhere, click, or press Space or Enter on the focused forest.
• Dotted guides mark the edges of the tower top, and quick logs trail speed lines. This is a visual timing game.
• A screen reader hears each landing, Perfect streaks, milestones, and the final height and score.
• Reduced motion stops the screen shake, drifting leaves, sparkles, and twinkling; the swinging log and the rising camera remain.
• Optional sound and pause are in the toolbar. Every label is at least 12 pixels on phones.

Guides and roundups

• Mossy Stack Guide: Perfect Drops and Streaks
• Quick Free Games to Play When Bored at Work