You pick one of eight racers and race seven computer drivers around a coastal circuit, drifting through corners for speed boosts and picking up items from rainbow boxes: shells, bananas, mushrooms, a star, lightning. It is modelled on Mario Kart, and the author's README says five Claude Opus 5.5 sub-agents built all of it from a single prompt. Open source under the MIT licence; keyboard only.
Turbo Kart Rally is a 3D kart racer that runs in the browser. You pick one of eight racers, a class (50cc, 100cc or 150cc, which sets how good the computer drivers are) and 1, 3 or 5 laps, then race seven computer-driven karts around a single track called Palm Cove Circuit. Corners are taken with a hop and a drift, and a long drift pays out as a speed boost when you let go. Rainbow item boxes along the road give you shells, bananas, mushrooms and the rest of a familiar arcade kit to use on whoever is ahead of you. The track data in the game gives a length of 2,116 metres, 8 boost pads, 2 jump ramps and 30 item boxes, which matches what the README says.
It is a homage to Mario Kart, and it does not hide that. The prompt the author reproduces in the README asks for "a clone of Mario Kart". The README's disclaimer then calls the game an original, fan-made homage to the kart-racing genre, not connected to Nintendo, with all characters, circuits, names, art, music and code original. What we can say from playing it: the item set is the Mario Kart one (the README lists mushroom, triple mushroom, banana, green shell, homing red shell, star, lightning and blue shell, and the code has the same eight; we saw the mushroom and the green shell in play), the item boxes are rainbow cubes, and the eight racers are drawn so that anyone who knows that series will think of its cast: a red cap with a B on it, a green cap with a Z, a crowned blonde, a white mushroom cap with blue spots, a horned green reptile, a yellow cap, a blue-green figure in a shell-shaped helmet. None of them carries a Nintendo name (the design notes in the repository say the game uses original material only, with no Nintendo names, characters, logos or assets), and we found none in the code. We do not say who they are meant to be; look at the picture on the racer screen and judge. If you are a rights holder and have a concern, use the contact in this site's footer.
It is here because of who says it wrote it. The README says the whole game was produced by five Claude Opus 5.5 sub-agents working in parallel from a single prompt, without a follow-up question, and prints that prompt: launch five Opus 5.5 sub-agents, build a Mario Kart clone in three.js, ask no questions. The author, BridgeMind (@bridgemindai on X), posted the game on 22 September 2026 with the line "Claude Opus 5.5 just ONE SHOT a Mario Kart game." The post also says Mario and Luigi are in the game and playable. The published game has no racers with those names, and the README says every character is original, so the post and the published build do not match on that point. We did not watch the video attached to the post, so we cannot say what it showed. The credit is therefore the author's own word, in the README and in that post. We cannot see how the game was actually made: the repository has a single commit, "Initial release", dated 22 September 2026, so its history shows nothing about the process.
How to play Turbo Kart Rally
- Press Enter or click on the title screen. Choose a racer with the arrow keys or the mouse, then set the class and the number of laps to the right and press RACE!. Blaze, Zippy, Bella, Toadly, Rex, Grumbo, Koopz and Dotty each have their own bars for speed, acceleration, handling and weight. The last choice is remembered next time.
- A short flyover of the track plays first (Enter skips it), then start lights count down to GO. The README says that holding accelerate as the count reaches GO gives a rocket start; we did not test that.
- Hold W or Up to drive and steer with A and D or the arrow keys. Tap Space to hop, and hold it through a corner to drift: the README says the sparks turn blue, then orange, then purple, and that a longer drift gives a bigger boost on release. The README also lists boost pads, jump ramps with trick boosts, a slowdown off the road and bumps when you hit a wall or another kart.
- Drive through an item box and a roulette in the top middle of the screen picks an item for you. Press E, X or Left Shift to use it. The README says the odds depend on your position, so you tend to get the stronger items when you are behind.
- Esc or P pauses, with buttons for Resume, Restart and Quit to Menu and the control list underneath. M mutes. When the race ends there is a results table of all eight racers with RACE AGAIN and MAIN MENU buttons. Drivers who had not yet finished when we ended a race early were shown with a ~ before their time, which looks like an estimate.
Controls: W or Up accelerates, S or Down brakes and reverses, A and D or Left and Right steer. Space hops and, held through a corner, drifts; let go for a speed boost. E, X or Left Shift uses the item you are holding. C looks back, Esc or P pauses, M mutes. Enter or a click starts from the title screen and Enter skips the flyover before a race. A gamepad is also read, per the README and the code; we did not try one.
Click Fullscreen above the game for the largest play area. If the game does not load, use Open in new tab to play it directly from our copy.
Why it's worth your time
Where this copy comes from. The Play button runs our copy of the author's GitHub Pages site (bridge-mind.github.io/turbo-kart-rally), captured on 24 September 2026, 36 files and about 1.9 MB with the licence. The page and all 17 script files and the stylesheet are byte for byte what is in the public repository at its only commit (c52aca3), apart from the standard mirror script we add to the start page and the addresses of three.js and the fonts, which we point at our own copies. The original page loads three.js r170 from the jsDelivr network and two fonts (Lilita One and Nunito) from Google Fonts, so it needs a connection. Our copy holds those files as well, and ran with every request to another site blocked. The repository has an MIT licence file, copyright BridgeMind, and we keep it beside the game files. The original address stays linked.
Nothing to download but code. The README says every model, texture, sound effect and music track is generated in code when the page loads, with no asset files, and that matches what we captured: the game is JavaScript and one stylesheet, three.js and a handful of its add-on modules, and two font files. There is no image, audio or 3D-model file in the copy. The sound is made in the browser with the Web Audio API and starts on your first click or key press. We did not listen to it, so we cannot describe how it sounds.
How it ran for us. In Chromium on a Mac with an Apple M4, at 1280 by 720, it held about 60 frames a second on the title screen and about 54 in a race, with other programs running at the same time; the speedometer read between 137 and 165 km/h in the moments we looked. It needs WebGL2, which the README also says. We did not try it on a machine that draws in software, or on any other browser than Chromium.
It is a complete race, start to finish. We ran a one-lap race with a small script that pressed the keyboard the way a player would, steering toward the track's centre line: the intro, the countdown, the lap, the finish and the results table all worked, and the lap took 57 seconds. The script was not a good driver (it hit a wall about halfway and came in eighth of eight), which says something about our script and nothing about the game. We also switched on the game's own autopilot and watched it drive for about half a minute, and saw the position list, lap counter, minimap, item roulette and speedometer update as they should. We did not play a full three or five laps ourselves, and we did not try the 50cc or 150cc classes.
What it keeps and what it sends. It stores one thing in your browser, your last racer, class and lap count, under the name tkr-settings, and it sets no cookies. In our copy the only requests were for its own files. There is no analytics or tracking code in the source that we could find. The original page, as noted above, calls jsDelivr and Google Fonts.
Phone and touch. The game has no touch controls. In an emulated iPhone 13 we could tap through the title screen and the racer screen and start a race, and the intro and countdown ran on their own, but once the race began the kart did not move whatever we tapped. So it is a desktop game with a keyboard, which is also how the README describes playing it. Held upright, the RACE! button is below the bottom of the screen and needs a scroll. We tried this in an emulator, not on a real phone.
A debug hook. The README points out that window.__game in the browser console has helpers such as startRace(), toFinalLap() and finishPlayer(), and a debug.autopilot switch that drives the player's kart for you. We used the autopilot to get the picture on this page's card, taken about half a minute into a race on our copy, with the game driving. They do nothing unless you type them into the console.
What we could not check: the gamepad; the sound; each of the eight items (we saw the mushroom and the green shell held, and one mushroom used); the rocket start and the colours of the drift sparks; the 50cc and 150cc classes; a five-lap race; the video in the author's post; and, above all, how the game was made. The README's account of five sub-agents that each owned a set of files matches the file list in the repository and the design document in it, but that is the description of the result, not evidence of the process.
How it was made and where it lives
Published on GitHub Pages from a public repository. The author publishes as BridgeMind. Original: https://bridge-mind.github.io/turbo-kart-rally/. The Play button above runs our own unmodified copy, so the game keeps working here if that page goes down — which on free hosting usually has nothing to do with the author. Nothing about the game itself is changed, and the original stays linked from every page.
If you like Turbo Kart Rally, try these
For another arcade racer with drifting and items, Feiche 3D is an unofficial recreation of Tencent's QQ Speed in one page, also tagged Made with Claude Opus 5.5 (its page says on whose word). OVERDRIVE is a racing garage with twelve cars and nineteen tracks, and WaveRunner: Cala Coast is a calmer timed lap on a jet ski. For the other Mario-flavoured game on this site, Super Mario · Mushroom Kingdom is a pixel-art platformer, and Voxel Musou — Zhao Yun is a fan game from the same open-source, made-with-Claude corner of the site.
Frequently asked questions
- Is it free, and do I need to install anything?
- It is free and open source under the MIT licence, and it runs in a desktop browser with WebGL2. There is nothing to install and no account.
- Is it a copy of Mario Kart?
- It follows Mario Kart closely in its items, its item boxes, its drift-and-boost driving and the look of its racers, and the author's own prompt asked for a clone of it. But it is a different game with its own name, its own track and its own racer names, and the repository's design notes say it uses no Nintendo names, characters, logos or assets. We found none in the code, and the copy has no image or sound files at all.
- Who made it, and with what?
- BridgeMind (@bridgemindai on X, and the GitHub account bridge-mind). The README says five Claude Opus 5.5 sub-agents built the whole game from one prompt, and the author's post of 22 September 2026 says Claude Opus 5.5 "one shot" it. Both are the author's own statements; we cannot check how it was made, and the post's claim that Mario and Luigi are playable does not match the published game.
- Does it work on a phone or a tablet?
- Not to play. The menus can be tapped and a race starts, but there are no touch controls and the kart stays still. It needs a keyboard or a gamepad. We tested only an emulated iPhone, not a real one.
- Does it work offline?
- Our copy does: it ran with every request to another site blocked. The original page loads three.js from jsDelivr and its two fonts from Google Fonts, so it needs a connection.
- Does it save anything?
- Only your last racer, class and number of laps, in your browser's local storage under tkr-settings. It sets no cookies and has no accounts or scores online.
- How long is a race?
- A lap of Palm Cove Circuit took our script about 57 seconds at the 100cc class, so three laps is a few minutes. You can choose 1, 3 or 5 laps.
- Can I play with a gamepad or against other people?
- The README and the code say a gamepad works (we did not try one). There is no multiplayer: you race seven computer drivers.
- Is Turbo Kart Rally free to play?
- Yes. Everything on Floating Arcade is free, with no account, ads or downloads.
- Can I embed this game on my own website?
- Yes — copy the snippet below. The embedded player links back here, which is how we ask to be credited.
Embed Turbo Kart Rally on your site
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