How to play Onespark: rules and chain-reaction strategy
Everything you need to play Onespark, plus tips to get a better score.
How to play
- Set off every bomb on the board with a single spark, using as few extra bombs as possible.
- Each bomb shows its blast: + hits the 4 squares beside it, × the 4 diagonal squares, ✱ all 8 squares around it, and a red crate blasts in a straight line in its arrow's direction until a wall or the edge.
- A bomb caught in a blast goes off too, and so on down the chain. Bombs that can't reach each other form separate groups: two on Monday, up to four at the weekend.
- Arrow crates fire one way only and can't be turned. Their blast goes straight through bombs (setting them off) and through vases (breaking them), and only stops at a wall or the edge of the board.
- Walls stop arrow blasts, and nothing can be placed on them. They don't stop +, × or ✱ blasts.
- Drag the day's extra bombs from the tray onto empty squares (or tap one, then tap a square). Only empty plank squares take a bomb: not walls, vases or other bombs. The tray always holds more bombs than you need.
- Your extra bombs have a gold ring. They must go off too, and you can light the spark on one of them. Tap an extra bomb to put it back in the tray, or drag it to move it.
- Press and hold any bomb (or place one) to see its blast: orange squares are hit, an orange ring means that bomb would go off, a red square with a shaking vase means it would break. A grey, see-through bomb can't go on that square.
- Tap Spark, then the bomb to light (tap Spark again to cancel). You can test as often as you like: after each try the board comes back as it was, with your extra bombs still in place. Bombs that wobble after a try didn't go off.
- From Wednesday there are porcelain vases (one on Wednesday, up to three on Sunday). No blast may reach them: if one breaks, the chain stops with a "Crash!" and the try fails.
- The first spark that sets off every bomb ("All clear!") ends the game by itself at par. With more extra bombs a Finish button appears: hand it in, or undo the spark and try with fewer.
- Par is the fewest extra bombs possible. Par gets ⭐⭐⭐, one more ⭐⭐, anything else ⭐. Your number of tries is shown too, but doesn't cost stars. The shared result shows 💣 extras used (par) · sparks, and one 💥 per explosion of the winning chain.
- On a computer: keys 1 to 4 pick a tray bomb, the arrow keys move around the board, Enter places or puts back a bomb, S turns on the spark and Enter lights the bomb you are on, Escape cancels.
- In Settings you can turn on "Reduce flashes and shaking" (no white flash, no board shake), and turn explosion sounds and vibration off. The ? button opens the legend, where you can replay the tutorial.
Strategy: find the fuse end, then bridge the gaps
Start by reading the groups. Bombs that blast each other form a group; the board has two to four groups that can't reach each other. One extra bomb is usually needed for each gap between groups.
Not every bomb of a group lights the whole group. Arrows only fire one way, so a group with an arrow has a fuse end: the bomb that starts everything. Hold a bomb to see its blast and trace the chain backwards to find that end.
An extra bomb joins two groups when a bomb of the first group blasts its square and its own blast reaches the fuse end of the second group. So look for a square that one group already hits and that sits right next to (or in line with) the other group's fuse end.
Pick the shape that fits the gap. A wave (✱) reaches the most squares, which makes it the obvious pick… and the most dangerous next to a vase. A cross or a diagonal often threads between a vase and a bomb.
Example: two groups with a one-square gap, and a vase diagonally below the gap. 💣⬜💣 ⬜⬜🏺 A wave in the gap would blast the vase. A cross there reaches the bombs on both sides and misses the vase.
The tray always holds more bombs than you need, so choosing is part of the puzzle. Testing is free: place, spark, watch where the chain stops, adjust.