About Rampart Forge
One person makes the decisions; a team of AI agents writes the code and tests. Every step goes through the same stages: a plan, a check and acceptance.
About the studio
Rampart Forge is a one-person indie studio making 3D games for Android phones. I come up with each game and its rules and make every decision. A team of AI agents built on Claude, by Anthropic, writes the code and the tests and helps with the art.
My first game is Catapultia: Castle Battle, a turn-based castle duel for two players. It went into closed testing on Google Play on 31 October 2026, on the tenth day of work.
My games have no ads or in-app purchases, and nobody can pay to win.
How I work with AI agents
I approve every step as a plan and accept every result myself.
The agents write the code, the tests and the helper tools. They make the builds, capture frames from the running game to check them, and write reports. When a step changes the game’s logic, a second model reviews it separately.
The order of every step
- A short plan says what the step will change.
- I read the plan and give my ok. Work starts only after that.
- The agents do the work: code, tests and tools.
- The step is checked. The build must have no warnings, the automated tests must pass, and the game is launched and a frame captured. At checkpoints I also play it on a phone.
- The agents write a short report on what was done and what the checks showed.
- I accept the step, and only then is it done.
By 31 October 2026 Catapultia had 799 automated tests covering the rules, the flight of shots, destruction, the economy, the network and data. An auto-player runs the game without graphics and plays hundreds of matches against itself in a row; that is how the weapon balance was checked.
Art and sound
Music and sound effects were generated with ElevenLabs. The weapon concepts, the game icon and the store art were made with Gemini. I made the trees for the forest myself: a picture in Gemini, then a 3D model in Meshy. The characters at the weapons, the grass and part of the scenery come from the KayKit and Kenney asset packs, released under CC0. The full list of credits is on the Catapultia page.
Pace
The work took ten days, from the first concept on 22 October 2026 to the closed test on Google Play on 31 October. The devlog follows those days one by one.
What makes Catapultia different
Buildings collapse cube by cube. Everything is built from 10 cm cubes, and whatever loses support falls. Knock out the bottom row and the top comes down.
Hitting the target is a skill. There is no aiming line, only your own flags and the numbers from your last shot. The wind changes every fourth turn and breaks the numbers you memorised, so every match starts with ranging in again.
The build is secret, as in Battleship. Your opponent doesn’t see where your heart is or which side your weapon stands on until the battle starts.
The three weapons play differently, and none of them is simply the best. In balance tests the catapult won 53% of its matches against the other two, and the trebuchet and the ballista 48% each.
There are two ways to win: break the heart or burn it. A water barrel is the answer to fire.
An opponent you meet by room code is always a real person, and the computer opponent knows only what a player can see.
The server decides everything. The match plays out the same on both phones, and after a dropped connection you can get back into it.
Catapultia is in closed testing now. The game page has the screenshots, and the devlog has the story so far, with an RSS feed.