Math Attack makes arithmetic practice into a Missile Command-style city defense game

On 24 January 2017, a developer posting as Sanctor shared 'Show HN: Math Attack – My side project of 3 years', linking an Android game he had built in Unity3D over about three years of spare time. The idea is arithmetic practice recast as arcade defense: balloons carrying numbers float upward while bombs fall on a pixel-art city, and the player assembles an equation whose result matches each incoming bomb before it lands — a mechanic the author traced to Missile Command.

Every visual asset was made from scratch, sound effects came from free sites, and the game carried a day/night cycle in which city lights switch on, crickets chirp at night and birds tweet by day — details the author admitted served no purpose other than atmosphere. The free version was ad-supported, but ads appeared only after the player lost, never during play; a girlfriend-drawn anime mascot and retro high-score screens completed the look.

The thread reached 292 points and 113 comments. Reviewers called the game fun and praised the craft, but the clearest signal was from parents: dozens said they would gladly pay for an ad-free edition because they would not let children play games with interstitials. The author agreed during the conversation, released the Math Attack Education version the same day, and said the biggest lesson of the project was to release earlier and iterate with real feedback.

Within the thread he also admitted to about $3 of ad revenue since posting, planned a practice mode with selectable operations, difficulty levels, unlockable skins and localization, and noted that an iOS port waited on the $100 Apple developer fee. What made the idea stand was the transfer: mental arithmetic under time pressure is the entire game, so the skill being drilled is also the thing that saves the city.