SAVE IT AS A FILE IN THE PROJECT FOLDER, NOT AS A CHAT MESSAGE.
THEN: /goal build this in three.js, read SPEC.md and follow it
exactly, especially section 9.

{ START }

1 THE LOOK

bright low poly, the way a modern mobile adventure looks. flat
single colour surfaces, no textures, no photorealism. every shape
chunky and rounded, built from big simple volumes. soft round
shadows, not sharp ones. every colour saturated and warm, nothing
washed out.

sand: warm cream, almost yellow
shallow water: bright turquoise. deep water: strong teal
palm leaves: fresh green. trunks: light brown
rock: warm sandstone, dusty ochre, never cold or blue
the crab: deep coral red, darker at every joint
its shell: pale bone white, the only near white in the scene

clear gradient blue sky, three or four soft rounded clouds. sun
high and slightly behind the camera.
if a surface looks detailed, simplify it.

2 THE CHARACTER

the player is a crab. both claws are the same build and the same
size, and each has to read as a pincer at a glance.

a crab claw is flattened side to side: narrow across, tall, long
along its own axis. built as a cube it reads as a box on a stick.

build each claw from four parts, sized against the body width:

1 upper arm. a rounded cylinder from the side of the body.
  length 0.30, thickness 0.27.
2 palm. a rounded box, flattened across: width 0.34, height
  0.64, depth 0.54. depth is the long axis, running out along
  the claw.
3 fixed finger. grows out of the top front of the palm, length
  0.80 of the palm depth. fat at the base, tapering, and hooked
  hard downward over its last third.
4 moving finger. the same shape mirrored below, hinged at the
  palm, hooking up. the two are carried about sixty degrees
  apart, so the pair reads as an open crescent.

swing the claw 54 degrees out from the walking direction. not
forward, because the camera rides behind and a forward claw is
seen end on with the palm hiding the fingers. not ninety, which
reads as a fork stuck out sideways.

forbidden for the claw: no flat blades, no thin plates, no
spikes, no arrow or dart shapes, no fins, no cube shaped palm,
no fingers shorter than half the palm, no straight fingers.

it carries a shell that is not its own. on the rear half of its
back sits a smooth dome of pale bone white stone, flat on top,
with seven shallow round sockets cut into it in a ring. the dome
sits behind the eyes and never over them: a shell on the back,
not a helmet and not a face.

the sockets are empty at the start. every crystal shard the crab
picks up drops into the next socket and stays lit. by the end
the shell is a ring of seven lights and the crab is visibly a
different character than it started as.

the body is a rounded wedge, wider than tall. six short legs.
two eyes on short stalks on the body, never on the shell.

it faces the direction it is travelling and the camera sits
behind it. six legs scuttle. turning sharply, it plants a claw
and pivots around it.

standing still, it taps a claw tip against the sand, twice, then
waits. that tap is the character.

3 THE WORLD

a small tropical island seen from a low three quarter view. the
playable area is a curved beach wrapping the island, water on one
side and land on the other.

a wide sand strip with a wet darker band at the waterline. palm
trees, every one leaning differently, never two the same height.
warm sandstone boulders, some standing in the shallows. driftwood
logs. a short wooden jetty. a cave mouth in a sandstone face at
one end. low green bushes in clumps along the back of the beach,
chunky rounded leaves, flat colour, no individual blades. seven
wooden chests scattered along the beach, closed. starfish and
shells as small props.

small waves push in and out in a slow loop. palm leaves sway.
nothing else moves on its own.

4 THE ACTIONS, DESCRIBED ONLY THROUGH USES

the crab scuttles across the sand and old dull gold coins lift
off the ground, arc toward it and vanish into it as it passes. it
never has to touch them exactly.

the crab enters the shallow water and its legs kick up small
white splashes.

the crab reaches a driftwood log, hops it, lands with a puff of
sand.

the crab enters the cave mouth and the inside lights up around
it.

the crab taps a wooden chest twice with a claw, the lid throws
open and what is inside rises out.

the crab touches a crystal shard. the shard rises, spins once,
and drops into the next empty socket on its shell, where it stays
lit for the rest of the game.

show all of this happening. never explain it in a caption.

5 THE GOAL

seven crystal shards are hidden around the island. collecting all
seven fills the shell and finishes the game.

placed in rising difficulty:
1 in plain sight on open sand, so the player learns the shape
2 behind a clump of palms, seen only when walking past
3 at the end of the wooden jetty
4 in the shallows, half covered by a boulder
5 inside the cave mouth
6 on top of a rock the crab has to hop up to reach
7 inside the seventh chest

no two shards are the same colour. in order: amber, rose, violet,
deep blue, sea green, pale ice, and the last one burning orange.
the shell lights up in those colours as they land.

six of the seven chests hold a pile of coins, the seventh holds
the last shard. an opened chest stays open.

coins are everywhere and never required. they exist to make the
space between shards worth crossing.

6 THE INTERFACE

a HUD is allowed. nothing else is.

top left: a coin icon and a number, a shard icon and a count out
of seven. top right: one short line naming the objective.

no health bar, no timer, no minimap, no joystick graphic, no
tutorial popup, no floating labels in the world, no speech, no
captions explaining what just happened.

when the seventh shard lands, the objective line is replaced by a
single line saying the island is clear.

7 THE CAMERA

behind the crab and slightly above, roughly four crab lengths
back, angled down about thirty degrees. it never leaves the crab.
no cutscenes, no fly overs, no establishing shots, no orbits.
passing close to a palm trunk, it eases in, then back out.

8 NOTHING REPEATS

no two palms share a height, a lean, or a leaf count. no two
boulders share a silhouette. the seven shards differ in colour
and in the shape of the cut. the beach is never symmetrical: the
jetty sits at one third of its length, the cave at the far end,
never centred. the crab is the only red object in the world. the
shell is the only near white surface.

9 BANNED, EACH ONE NAMED

gameplay: no enemies, no combat, no health, no damage, no dying,
no timer, no score multiplier, no lives, no shop, no upgrades, no
dialogue, no cutscene, no loading screen art.

character: no spiral snail shell, no googly eyes, no hat, no
clothing, no backpack, no face on the shell, no cartoon eyebrows,
no sunglasses.

scene: no beach umbrella, no deck chair, no pirate flag, no
message in a bottle, no seagulls, no crabs other than the player,
no fish, no beach ball, no sandcastle, no footprints trail, no
floating bubbles.

repeats of my earlier build: no grass field, no mushrooms, no
wooden crates, no red round trees, no rolling green hills.

render: no realistic textures, no snow, no desert, no night, no
sunset, no rain, no fog, no lens flare, no film grain, no
letterboxing, no depth of field blur.

{ END }

that fourth group is the one nobody writes. those five are from a
game I shipped in august. without them the model rebuilds it.