Mutant Sandbox

Cinevva's analyzer read this game's design doc and its source, then wrote the brief below. "Make your own" hands it to the game creator as your opening message, so you start from a real spec rather than a one-line idea.

Create a browser-based 3D simulation sandbox titled “Mutant Sandbox” using Three.js. Show a contained square laboratory arena from a floating third-person research-drone camera: the camera is around y=9, follows the drone, looks forward toward the ground, and has a centered glowing mint crosshair. The arena is a dark green 90x90 flat plane with a subtle green grid, low dark-green perimeter walls, fog, soft shadows, and moody green laboratory lighting. Keep the camera/gameplay visually close to a simple low-poly neon-green science sandbox.

Start with 10 creatures, 16 ordinary food items, and 4 purple rich/mutagen food items distributed around the arena. Creatures are stylized low-poly mutants made from a large squashed colored sphere body, a smaller head, two bright eyes, individually generated pale cone horns, and multiple dark legs. Their DNA traits control size, movement speed, aggression, hunger/food-seeking range, hue/color, horn count, leg count, and glow. Use green/cyan/blue/purple hues with emissive highlights. Creatures bob gently while moving, wander to random targets when not hungry, and seek nearby food when hungry. Food is a floating, rotating low-poly icosahedron: ordinary food is glowing lime green and restores 22 energy; rich food is glowing magenta/purple, restores 40 energy, and mutates the creature that eats it.

Implement the simulation rules. Each creature has energy, age, a name, DNA, and a reproduction cooldown. Energy drains continuously based on speed and size. If energy reaches zero or age exceeds 150 seconds, remove the creature. Creatures with aggression above 0.68 chase nearby smaller rivals and drain their energy. If a creature has over 112 energy, its cooldown is ready, and the population is below 34, spend energy and spawn a child nearby with inherited DNA plus random mutations. Mutations vary size, speed, aggression, hunger, hue, glow, horns, and legs within sensible bounds; generation increases as reproduction occurs. Keep the population from becoming permanently empty by occasionally adding creatures, and occasionally add food when fewer than 8 remain.

Place three visible animated lab machines around the arena, each on a round dark metallic platform with a column, console/screen, transparent chamber, glowing core, rotating luminous ring, beam, and a floating canvas-style label. Put a lime “FEEDER” at approximately (-29,-25), a magenta “MUTATOR” at (29,-24), and a blue “SCANNER” at (0,31). The feeder attracts creatures within 13 units, slowly restores their energy, and periodically spawns ordinary food nearby. The mutator periodically mutates creatures within 9 units. The scanner automatically selects the nearest creature within 10 units and slightly restores it while its beam points toward the subject. Add expanding fading ring splash effects when creatures eat, reproduce, mutate, or die.

Controls: WASD and arrow keys move the floating research drone; Q/E rotate its view in small increments; Space drops one purple rich food at the center crosshair; clicking/tapping the ground drops ordinary green food (shift/alt click may drop rich food). Support mobile with a circular on-screen joystick at bottom right. Add HUD buttons: “Add creature” creates one near the drone, “Drop food” drops five ordinary foods at the center of view, “Mutagen pulse” mutates nearby creatures (and some random others) and creates six purple foods around the arena, and “Reset” restores the initial population and food setup. Clicking/tapping a creature selects it instead of dropping food.

Build a fixed responsive HUD over the canvas. At top left, use a translucent dark-green panel with a thin mint border showing: bold green “Mutant Sandbox”, creature count, food count, generation, and averages for size, speed, and aggression. When selected, show the creature’s name and DNA values for size, speed, aggression, horns, and legs. Include instructional text: “Click a creature to inspect it. Purple food mutates. Green food feeds. Mutated survivors reproduce with changed DNA.” At top/right or wrapped below on small screens, use rectangular dark-green bordered buttons. At bottom left, show: “Sandbox: WASD/arrow keys or joystick to move the research drone. Click/tap ground to drop glowing food. Mutagen pulses scramble DNA — watch size, speed, color, horns, legs, and aggression evolve.” On mobile move this panel above the joystick and show a translucent circular joystick with a bright mint center stick. Use pointer-event-safe UI so buttons/joystick do not accidentally place food. Expose getGameState/setGameState-style debug APIs for counts, generation, player position, selected creature, averages, pause, and basic population/food adjustment.