あと一番出口
A short first-person anomaly game that starts at the very last stage of “some game”; its developer says Gemini CLI wrote all the code and drove the Unity editor.
Official site unityroom.com, verified Nov 3, 2026. Linked from the developer's own Qiita devlog; the unityroom page is posted by the developer's account ryuryu and links back to that devlog.
Where to play
Every platform this game is on. Links are checked against official sources; we never host or mirror games.
- Play free — official siteBrowserReleased · Unity WebGL build hosted on unityroom, a Japanese free-game site we do not track as a platform; tagged as smartphone-ready, though the page suggests trying a PC if it does not run.Free
Runs in a desktop or mobile browser. No download.
Browser (no download) · Mobile · Official link verified Nov 3, 2026.
About あと一番出口
A free first-person anomaly-spotting game in the browser, made for unityroom's Unity 1-Week Game Jam on the theme “もうひとつ” (one more). You wake up at the final stage of an unnamed game, one step from clearing it, and the rule is the familiar one: if anything has changed, turn back; if nothing has, go forward. The developer's concept note describes it as a game in the style of The Exit 8 (8番出口), and its unityroom page is tagged 8番ライク; it is an independent jam game, not affiliated with that title. You move with clicks only (forward, back, turn around), and later unlock a scan you trigger by long-pressing suspicious spots; per the in-game hint, an anomaly you have scanned once appears much less often. The unityroom page puts a playthrough at about 30 minutes, and the developer's replies to players mention several endings. The text is in Japanese. The developer says that Gemini CLI, connected to the Unity editor through the uLoopMCP server, wrote all the code and handled the editor work, so the developer wrote no code and barely touched Unity.
How it was built
VerifiedThe developer's Qiita devlog says Gemini CLI was the AI agent for the whole build, connected to the Unity editor through uLoopMCP, an MCP server that lets the agent compile, run menu items and dynamic C# code, and place and move objects in the scene. The developer left implementation and editor work to Gemini, had it compile after every change and check the logs, then tested each feature by hand before asking for the next one. The model setting was Auto (Gemini 3) on a paid Gemini AI Pro plan. A project file (GEMINI.md) and a Docs folder of concept, plan, progress and technical notes kept the agent on track across restarts; the developer reset the session by hand as features were added because answers got worse as the context grew. Gemini also read unityroom's documentation itself to add the online leaderboard. Before building, the developer brainstormed ideas with the Gemini chat app and had it mock up quick HTML prototypes with its Canvas feature. The developer says the agent choice matters less than its ability to connect to an MCP server.
- DeveloperThe unityroom game page lists the Qiita devlog (“Gemini CLI+uLoopMCP”, made without writing any code) as its related article. — unityroom
Agent-driven Unity development for a game jam. The developer spent about six days on the concept and about three days on implementation, finishing after the jam's development deadline (the developer calls it late). Implementation followed a loop: get a minimal version running, then ask for one feature at a time, with the agent compiling and checking logs and the developer playtesting by hand. Git and automated tests were skipped as a short personal project; the developer tried automating tests through uLoopMCP but found manual checks faster for this game. When the agent misbehaved during long debugging, the developer had it analyse what went wrong and added the lesson to GEMINI.md. The developer puts the cost at about ¥1,500 for the Gemini plan plus about US$20 of assets, and says the uLoopMCP setup made this far easier than the developer's previous jam entry.
- Engine / framework
- Unity
- Languages
- C#
- Team size
- 1 (solo)Developer ReportedQiita (NNNiNiNNN)
- Initial build time
- About 6 days of planning and about 3 days of implementationDeveloper ReportedQiita (NNNiNiNNN)
- Development time
- Not disclosed
- Development cost
- Not disclosed
- AI-written code
- Not disclosed
“【Gemini CLI+uLoopMCP】コードを一切書かず、Unityの操作もせずに、3日でゲームを作った話【Unity1Week】”Verification notes: AI use from the developer's Qiita devlog (posted 6 Jan 2026, updated 11 Jan), which links the unityroom game page twice; the unityroom page, posted by the account ryuryu, links the devlog as its related article, so we treat ryuryu and the Qiita user NNNiNiNNN as the same developer. Jam entry, theme, posting date (30 Dec 2025) and update notes from the unityroom page; the jam's development period (21–28 Dec 2025) from unityroom's event page. Whether the late entry was ranked is not stated, so no jam result is recorded. The cost is given in two currencies (about ¥1,500 for the Gemini plan plus about US$20 of assets), so no US$ total is recorded. The developer says no code was written by hand, but the game also uses purchased assets, so no AI code share is recorded. The unityroom page showed 11,882 views, 53 ratings and 19 comments on 3 Nov 2026 (observed; we have no metric kind for unityroom counts, so they are not recorded as metrics). No source mentions generative AI running in the game.
Development history
unityroom's Unity 1-Week Game Jam opens with the theme “もうひとつ” (development period to 28 Dec, 20:00 JST).
OfficialunityroomPosted free on unityroom as a jam entry, after the development deadline (the developer calls it late).
The developer publishes a Qiita devlog on building the game with Gemini CLI and uLoopMCP.
DeveloperQiita (NNNiNiNNN)Update so that progress is no longer lost when the browser page is reloaded.
DeveloperunityroomSmall change to the ending title.
Developerunityroom
Game performance
Each figure measures something different — concurrent players, owners, downloads and sales are never interchangeable and are never added together. Labels show where each number comes from.
Browser (official site)
No public metrics recorded for this listing.
Not publicly available: Concurrent players (site), Monthly revenue, Gross revenue.
Sales & revenue (all platforms)
Browser game — there are no downloads to count.
Reviews & rankings
Not yet reviewed by our editors.
Prototype: your vote is kept only in this browser and is not counted anywhere.
Not currently ranked.
No player reviews yet.
Prototype: reviews are stored in your browser only and are not published or sent to a server. Reviews are shown in the language they were written in.
Sources
| Source | Type | Published | Accessed |
|---|---|---|---|
| あと一番出口 | フリーゲーム投稿サイト unityroom unityroom · Japanese | Store page | Dec 30, 2025 | Nov 3, 2026 |
| 【Gemini CLI+uLoopMCP】コードを一切書かず、Unityの操作もせずに、3日でゲームを作った話【Unity1Week】 Qiita (NNNiNiNNN) · Japanese | Devlog | Jan 6, 2026 | Nov 3, 2026 |
| Unity 1週間ゲームジャム お題「もうひとつ」 unityroom · Japanese | Official site | Not confirmed | Nov 3, 2026 |
| Official game page (language check) unityroom (ryuryu) | Official site | Not confirmed | Nov 3, 2026 |
