A retro arcade shooter where the ammo is arithmetic. Hit a target number by blasting falling numbers and adding them up, but don't let them reach your ship. It's mental math disguised as an 80s space game.
You're given a target, like 15. Numbers drift down from the top of the screen. Every number you shoot is added to your running total. Land on the target exactly and you clear the round and get a new one. Simple sums, played at arcade speed.
Some numbers are negative, so you can always correct a miss: a target of 8 can be
reached as +4 +4 or +9 -1. Positives are blue, negatives are pink.
Clear a few rounds and the game steps up to Level 2, swapping in bigger denomination-style numbers (5, 10, 25, 50, 100, 250, 500), positive and negative, for tougher sums at a faster pace.
| Key | Action |
|---|---|
| Arrow keys | Move your ship left and right |
| Space | Fire |
| L | Peek at the leaderboard |
| M | Mute / unmute the sound |
| Q | Quit |
On a phone or tablet you can play with touch alone: drag left and right to move your ship, and tap anywhere to fire.
- Shoot numbers to add their value to your total (shown top-left).
- Reach the target exactly to score and move on.
- Use negatives to come back down if you overshoot.
- Don't get hit. A number that reaches your ship costs one of your three lives.
Clear enough rounds to fill the score bar and you win the run. The clock is always ticking, so the real challenge is finishing fast. Your best times go on the leaderboard, and the fastest run sits proudly at the top.
- Plan a couple of shots ahead: if the total is 11 and the target is 15, hunt for a +4 rather than blasting the first thing you see.
- Stuck just over the target? A negative number is your friend.
- Speed matters more than safety once you're good. The leaderboard rewards the bold.
Have fun, and mind the math.
Curious how it's built and how it runs as WebAssembly in the browser? See the
technical overview. The game's behavior is also captured as
validated capability specs under openspec/specs.