📀 PS22005Team IcoVERY HARD

Shadow of the Colossus rebuild deck

VERY HARD

Bone-space attachment is a lovely engineering problem an agent solves once you name it, and then you are left needing sixteen bespoke encounters that are each an animation authoring job.

You will get a good prototype. The product is what comes after.

A NOT REALLY that is still worth building, because the bone-space attachment problem is a genuinely great engineering exercise and an agent handles it well once you name it. What no prompt gives you is the sixteen encounters, the animation authoring, or the emotional design — this game is 60 team-years of restraint, and restraint does not come out of a text box.

Difficulty: VERY HARD · 4 of 5
First playable: A project
The original: 60 team-years
Released: 2005 · PS2
Genre: Action Adventure

The one-shot build prompt

Build a climbable-giant boss encounter prototype. three.js plus physics. Scope it to ONE colossus, done properly.

Requirements:
- The colossus is an animated skeletal mesh whose surface is climbable. When the player grips, attach them to the nearest bone with an offset, so they move with that bone through the animation. Every subsequent movement is expressed in bone-local space. This attachment system is the entire project — build it first with a simple animated cube before you model anything.
- Stamina: gripping drains a meter, releasing on empty drops you. The meter recovers only when standing on a flat surface or a resting hold. This turns a climb into a route-planning problem.
- The colossus animation must actively fight you: idle sway, shakes triggered when the player is on a limb, and a violent thrash on a timer. The player's grip position must survive all of it, which is what makes bone-space attachment mandatory.
- Weak points that must be reached and struck with a charged attack; damage staggers the colossus and briefly stops the thrashing.
- A horse companion with its own momentum-based controller that you steer by suggestion rather than direct control.
- Camera: the hardest part. It must frame a 40-metre creature and a 1.8-metre player at once, pulling out during a climb, and never clip through the colossus. Use a spring-arm with sphere-cast collision and a target that blends between player and colossus centre by distance.
- Art direction over fidelity: heavy bloom, desaturated palette, strong sun, and dust.

Definition of done: I climb an arm, the colossus thrashes, I hold on because I saved stamina, and the camera never loses either of us.

Before you start🧰 The toolkit — models, MCP servers, art and 3D

What you lose

Sixteen bosses that are each a hand-authored puzzle, animation set and encounter
The animation work — the grip, the sway, the exhaustion — which is the entire feeling
A world designed to be empty in a way that means something
The score, and the restraint to use it almost never

What to steal

Player attached to a moving bone

Once a character's position is stored relative to a bone rather than the world, everything the animator does to that bone is free: sway, thrash, a lift, a ship rolling in a swell, a rotating platform. Get it wrong and every moving surface in your game quietly slides the player off it.

ScopeA weekend— build just this, not the game

Build a moving-frame attachment toy. Single HTML file, three.js from a CDN import map, no build step, no physics engine.

Make one animated rig by hand: a torso with a two-jointed arm, driven by sine oscillators on each joint so it sways, plus a button that triggers a violent 1.5-second thrash. Deliberately do not smooth the thrash.

A capsule player can grab the arm's surface. On grab, resolve the contact point into the nearest bone's local space and store that offset. From then on, the player's world transform is bone matrix times offset, recomputed every frame after the animation updates. Input while attached moves the offset across the surface in bone-local coordinates, never world coordinates. Releasing drops the player back into plain world-space gravity.

Draw the attached bone's local axes while gripping, so the frame the player lives in is visible.

Definition of done: I hold on through a full thrash without sliding, and my grip stays on the same patch of surface throughout.

Make it different

Not a clone — Shadow of the Colossus re-themed and cut down to something you can finish. The angle is the important reel: it is what turns a project into a weekend. 24,360 ways to land.

Shogun Deck

Shadow of the Colossus, but a deckbuilder version of its combat, set in feudal Japan. Rendered in LEGO brick build.

Themefeudal Japan

Anglea deckbuilder version of its combat

LookLEGO brick build

Build a browser game called "Shogun Deck".

The pitch in one line: a action adventure in the spirit of Shadow of the Colossus, but a deckbuilder version of its combat, set in feudal Japan.

WHAT THIS IS
Take the SHAPE of Shadow of the Colossus — its core loop, and whatever makes that loop good — and rebuild it as your own game in a different world at a smaller scope. Use your own names, art and audio, which you want anyway: a reskin of somebody else's game is less interesting than a new one that works the same way.

THE ANGLE — this is the important constraint, honour it above everything else
A deckbuilder version of its combat. Every action becomes a card with a cost. Cards, relics and enemy intents are pure data, and the whole balance surface becomes a spreadsheet you can tune.
This is what makes the project finishable. If a decision would push the scope back towards the original's, take the smaller option every time.

THE THEME
Feudal Japan. Duels decided before the first strike, weather and season as mood, and restraint in everything including the interface.
The theme is not a coat of paint. Let it change what the mechanics mean — a reload, a health pack and a locked door should all be things that make sense in this world and nowhere else.

LOOK
LEGO brick build. Studded bricks, clutch-power joints, minifig scale proportions, and explosions that separate into pieces not polygons.

REQUIREMENTS
- Runs in a browser with no build step. Canvas 2D unless the angle genuinely requires 3D, in which case three.js.
- Fixed-timestep update loop with interpolated rendering, so it behaves the same at 60Hz and 144Hz.
- Every tuning constant in one CONFIG object at the top, exposed as live sliders in a debug panel. You will find the feel by dragging those, not by prompting.
- All content — levels, entities, balance numbers — in JSON or plain data files, never inline in the logic.
- Audio generated with the Web Audio API rather than asset files.
- Respect prefers-reduced-motion: keep the fades, drop the shake and the parallax.

BUILD ORDER
1. The core loop with placeholder rectangles, at the reduced scope the angle demands. No theme, no art, no audio. Make it fun as rectangles first.
2. The angle's consequences. Cutting to bots, or to turn-based, or to one level changes the design rather than just shrinking it — find out how and rewrite step 1.
3. The theme, as content and data.
4. The look, applied last as a rendering layer over a game that already works.

Start by writing a one-page plan: the core loop, what the angle removes and what that frees you to do properly, and what you are deliberately leaving out. Wait for me to approve it before writing code.

Prior art — read before you build

Half the time one of these already does what you wanted, and the other half it saves you a week of solving a problem someone documented in 1997.

Did you build it?

0Share on X

One count per game. No account — it is tied to a salted hash of your IP, which is not stored in a form anyone can reverse. Every build adds 60 team-years to the counter on the homepage.

Then try these

Or roll something nobody has built yet →

Questions

How hard is Shadow of the Colossus to rebuild with an AI agent?

Yes — every game is buildable at some scope. The question is how hard, and Shadow of the Colossus is VERY HARD (4 of 5). You will get a good prototype. The product is what comes after. Bone-space attachment is a lovely engineering problem an agent solves once you name it, and then you are left needing sixteen bespoke encounters that are each an animation authoring job. Reckon on a project to something you can actually play — not to something that matches the 60 team-years Team Ico spent.

What makes Shadow of the Colossus hard to rebuild?

Bone-space attachment is a lovely engineering problem an agent solves once you name it, and then you are left needing sixteen bespoke encounters that are each an animation authoring job. That is why it sits at VERY HARD rather than a tier either side of it. If you want the idea without the project, the transferable part is player attached to a moving bone — a weekend of work.

How long does it take to build a Shadow of the Colossus clone?

Wrong question, and it is worth saying why. Nobody rebuilds Shadow of the Colossus — the original took Team Ico on the order of 60 team-years, released in 2005 on PS2. What you can do is reach something playable and genuinely yours in about a project, and then keep going for as long as it stays interesting. Any figure that claims otherwise is measuring a prototype and calling it a game.

What do I lose by building my own Shadow of the Colossus?

Sixteen bosses that are each a hand-authored puzzle, animation set and encounter. The animation work — the grip, the sway, the exhaustion — which is the entire feeling. A world designed to be empty in a way that means something. Those are the parts a prompt will not hand you.

Which AI coding agent should I use to build it?

Any of Claude Code, Codex or Cursor will handle this prompt. Paste it as your first message, let the agent scaffold the project, then iterate on feel — the second, third and tenth prompts are where a game actually gets good. Work in an empty folder or a fresh git branch so you can throw it away cheaply.

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