Last Sector: Operation Blackridge — Claude Opus 5.5
An 800 m island, six locations, squads that flank and search, and a 25-second extraction hold. Desktop, mouse and keyboard.
About this project
A third-person tactical extraction shooter on Blackridge Island: a heightfield island with sea, cliffs, roads and a terraced quarry, six major locations plus four minor sites, and buildings you can enter with stairs and reachable roofs. Golden-hour light drifts to an overcast evening, with random clear, cloudy or light-rain weather.
Six fictional weapons with per-weapon recoil and falloff, head, torso and limb hitboxes, Frag Pulse and smoke that really blocks enemy sight, helmets and vests, healing that movement interrupts, a four-phase Signal Collapse and a 25-second extraction hold against assault waves. Enemies come in five archetypes and two factions, use cover, peek, flank campers, remember where they last saw you and eventually give up the search.
Why it was built
Part of Model Arena #03. Both Claude models received the exact same brief (shown on the Model Arena page) in a fresh session: build a complete 3D tactical extraction shooter that runs in a desktop browser.
How it was built
Built by Claude Opus 5.5 (effort: high) in a Claude Code cloud session from the Model Arena #03 brief, over 9 commits in about two hours: first all core systems, then passes on lighting and tone mapping, navigation, enemy accuracy, UI layout at 1366×768, a pointer-lock fix and the production build.
Stack: Three.js with TypeScript and Vite. A* navigation on a 1 m grid with carved doorways, hitscan traced from the shoulder so you cannot shoot through a wall you are behind, and pooled tracers, impacts and decals. Fonts are bundled locally and the whole build is about 1.4 MB.
Curated and published by Ezkielyna Lab. Want to build with the same model? Claude Opus 5.5 is available through Ezkielyna API as "claude-opus-5.5", with one key for every model: ezkielyna.store/api-credit
Notes
Notes from the model's REPORT.md:
Testing used Playwright driving headless Chromium. Bots completed full matches at several extraction sites, reaching Mission Complete after about 7.8 minutes of game time, and 24 of 24 navigation test paths reached their goals. Enemy hit rate falls from about 56% on a still target at 20 m to about 13% on a moving target, and a single enemy hit is capped so a headshot cannot one-shot a full-health player.
Known rough edges: the build machine had no GPU, so real frame rates could not be measured and some GPU-specific shadow or foliage artefacts may exist. Ctrl crouches but Ctrl+W closes the browser tab, so use C. Pointer lock depends on the browser; if it is refused the game falls back to unlocked mouse-look.
Feedback the maker is looking for
Desktop only: you need a mouse and keyboard. Play a full match in both versions. Which one has better shooting, smarter enemies and a world that feels more alive?
Comments are opening soon. Until then, share your thoughts in the community groups.
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More from Model Arena #03
Last Sector: Operation Blackridge — Claude Sonnet 5.5
A complete extraction loop on one shared heightfield: loot, fight squads, outrun the Signal Collapse, hold the extraction. Desktop, mouse and keyboard.
Claude Sonnet 5.5 · high · Claude Code
Ezkielyna Lab 1