Runner game maker

An endless runner is the arcade game people play in a waiting room: one more run, a little further each time. Describe your runner — the hero, the world, the obstacles — and the AI agent builds it as a real phone game. You play it in the emulator preview, tune the speed by chatting and download it as an Android APK. The idea above is a three-lane forest run; change the character and the world before you build.

What your runner game will have

The agent builds a complete run-and-dodge loop from the idea above:

• The world — a forest path that scrolls toward the player, with background layers that move at different speeds for depth.
• Swipe controls — left and right switch lanes, up jumps in a smooth arc, down slides under branches.
• Obstacles — logs to jump, branches to slide under and rocks that block a whole lane, placed so there is always a way through.
• Coins — in straight lines and arcs that reward good jumps, counted at the top of the screen.
• A difficulty curve — the speed climbs every ten seconds and gaps between obstacles shrink, up to a cap so the game stays playable.
• Game over and shop — distance, coins and best distance saved on the phone, plus a shop where coins unlock new fox skins.

Features you can ask for

• Power-ups: a coin magnet, a one-crash shield, a short double-coin boost.
• Missions such as "collect 200 coins in one run" or "jump 30 logs" with a reward for each.
• New worlds that unlock by distance: a snowy mountain, a desert canyon, a city at night.
• A day-to-night cycle during long runs.
• A "continue once" option that lets the player carry on after a crash by spending coins.
• Music and sound effects with separate mute switches.
• A marker on the track showing where your best run ended.

Ideas to make it yours

The simple game guide explains the most common runner mistake — speed tied to the frame rate — and how to describe a difficulty curve so it comes out right. When the game is ready for a store, the signed APK and AAB guide covers the package id, version and signing key.

Get it on your phone

1. Press Build this runner game and sign in with Google.
2. Play several runs in the emulator preview and note where it feels too easy or too hard.
3. Tune it in plain words: "start slower", "jump a bit higher", "fewer rocks in the first minute".
4. Press Download APK and install it on your Android phone to test the swipes with your thumb.
5. For Google Play, build the signed version from the same menu; the APK builder page explains it, and the Google Play publishing guide covers the listing.

Swipes feel different on a real phone than with a mouse. Install the APK early and test the controls with your thumb before you polish the art.

Tuning the difficulty curve

A runner is fun when the first twenty seconds are easy and the next two minutes get steadily tense. Tell the agent the numbers: the starting speed, how much it rises and when it stops rising. Ask for obstacles built from short hand-made patterns rather than pure chance, so there is never an impossible wall of rocks across all three lanes. Put the first coins in easy reach to teach the controls without a tutorial screen. Keep a crash fair: a slightly smaller hitbox than the picture makes near misses feel like skill, not luck. Then watch someone else play. If they die in the first ten seconds, slow the start; if they are bored after a minute, add a new obstacle type there.

Frequently asked