"Coral Keeper": a mobile game made in two months by 2 non-developer gamers with AI
"Coral Keeper," a mobile game made with AI by two gamers who are not developers, has launched on ONE store and in Toss. The game code was written by an AI coding tool (Claude), and the characters and background art were made by an image-generation AI (ChatGPT). The two of them decided which games are fun, played the game themselves, and told the AI what to fix. It took 58 days from the first prototype to the ONE store launch, and in the five days after launch they released 17 updates based on player feedback.
About the game
This is a vertical merge-defense game where you build a deck from 28 sea friends and protect the coral reef. Merging identical crew makes them stronger up to ★3, and crew that match an enemy's weakness deal 1.5× damage. Place pairs that really live together in nature, such as the Hermit Crab and the Anemone, side by side and both get stronger. The Codex lists 24 real crab species, including Snow Crab, King Crab, Coconut Crab, Japanese Spider Crab and Yeti Crab, and when you breed a male and a female, color variants such as Blue, Golden and Albino pass on to their offspring. The Ghost Crab, a protected marine species, is not caught and is only recorded as an observation.
Game info
| Item | Details |
|---|---|
| Game title | Coral Keeper |
| Developer | DNICHANI: a team of 2 non-developer gamers |
| How it was made | Code by AI (Claude) · art by AI (ChatGPT) · planning and review by people |
| Development period | 2026-08-14 to 2026-10-11 (58 days) |
| Genre | Merge defense + collection, vertical, one-handed play |
| Release | ONE store (Android 7.0 or higher, 2026-10-11), Apps in Toss (mini-apps inside the Toss app) |
| Price | Free (optional in-app purchases, no ads in the ONE store version) |
| Rating | All ages (ONIA-SG-261010-0002) |
Download
- Get it on ONE store
- Toss: search for "산호 수비대" (Coral Keeper) in the Toss app
Photo usage
You are free to use the photos below for articles and introductions. You can download them with "Get original." The AI development conversation images are reconstructions of actual development conversations, edited to be easier to read.
Contact
contact@zackson.kr: additional materials and interview requests are welcome.
