Arrow Stack is a free online maths game that runs in the browser with no download and no account. Your column of arrows runs down a corridor and every few metres a row of gates crosses it, one gate per lane, each carrying an operation — plus seven, times two, minus four, divided by two. Whichever lane you are in when you reach the row is the operation that applies, so each row is a piece of arithmetic taken at running speed. At the end is a wall of guards that needs a specific number of arrows to break through. The number on the wall is not a guess: it is worked out from an exact solver for every corridor, set between what the worst route would leave you and what the best one would, so it is always reachable and never accidental. Eight corridors run from two lanes of plus and minus to four lanes with multiply and divide in the mix.
How to play Arrow Stack
- Your column runs forward on its own. Tap a lane, or use the arrow keys, to move across.
- Each row of gates has one operation per lane. The lane you are in when the row arrives is the one that applies to your arrows.
- Green gates grow the column — plus and times. Red gates shrink it — minus and divide.
- Division rounds down, and the column never drops below one arrow, so a bad row is a setback rather than an ending.
- Every row has at least one gate that does not shrink you, so there is always a right answer.
- The wall at the end shows how many arrows it needs. Reach it with that many or more and you break through.
- The number on the wall is derived from the corridor: always achievable by the best line, always more than the worst line gives you.
- Three stars means finishing on the highest total the corridor allows — the after-run card tells you which lanes that route took.
Tips
- Multiply early, add late. Times two on ten arrows is worth ten; times two after you have added thirty is worth forty. Order matters more than any single gate.
- A times two beats almost any plus in the early rows, and almost no plus in the last one.
- Divide by two is not always wrong. If the alternative is minus nine on twelve arrows, the divide costs you less.
- Read the row after next. Lane changes are free and instant, so the only thing that limits you is knowing where you want to be.
- Count in round numbers. You rarely need the exact total, only which of two lanes leaves you more — and that is usually obvious at a glance.
- When two gates are close, take the one whose lane is nearer the middle. It leaves you a shorter move for whatever the next row demands.
- New Corridor generates a different set of gates at the same difficulty. Run Again repeats the identical corridor, which is how you chase the perfect line the summary card showed you.
FAQ
Is Arrow Stack free to play?
Yes. It runs in your browser with no download, no sign-up and nothing to buy. All eight corridors are included and unlock as you break their walls.
Is the wall always beatable?
Yes, and it is proved rather than assumed. Each corridor is solved exactly before you play it, and the wall is set below what the best route achieves and above what the worst route leaves you.
What happens if my arrows run out?
They cannot. The column never falls below one arrow, so a row of subtractions is a bad row rather than a lost run. You simply arrive at the wall short.
How does division work?
It rounds down and never takes you below one — nine arrows divided by two leaves four. That makes divide gates predictable, which matters when you are choosing at speed.
Is it better to multiply or add?
Almost always multiply early and add late, because a multiplier applies to everything you have collected so far. Working that out at running speed is the game.
Can I change lanes as often as I like?
Yes. Lane changes are instant and free — what limits you is reading the row ahead, not the movement.
How is this different from the other maths games here?
Most of them ask you to produce an answer. This one only asks you to compare two or three of them and pick the biggest, over and over, while the corridor keeps moving.
Does Arrow Stack work on a phone?
Yes. The lane buttons sit across the bottom of the screen, and the corridor is drawn into a portrait frame so you can see the next two rows of gates coming.