Direct a three-subagent team to build a genuinely playable Three.js game where a giant cat smashes a skyscraper city.
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You are the parent agent for this project. The model to use is GPT-6 Luna Max, and if possible stand up three sub-agents of the same Luna Max and use them in parallel.
The goal is to complete, centered on Three.js, "a genuinely playable browser game in which a giant cat rampages through a cluster of skyscrapers."
It must not be a mere physics demo, destruction simulator, or technical proof of concept; "being fun as a game" is the single most important requirement.
# 0. Agent structure
The parent agent is responsible for the overall design decisions, integration, prioritization, and final quality of the project.
First, stand up three Luna Max sub-agents, and in principle divide the responsibilities as follows.
## Subagent A: Gameplay / Game Design
Responsibilities:
- Game loop
- Controls
- Cat punch, movement, attacks
- Score
- Combos
- Objectives
- Risk and reward
- Difficulty
- Sense of satisfaction
- Feedback to the player
- Evaluating "game-likeness"
In particular, make sure it does not end up as merely "you can break buildings."
## Subagent B: Destruction / Physics / Technical
Responsibilities:
- Three.js-related technology
- Physics engine selection
- Building collapse
- Collisions
- Rubble
- Performance
- Object management
- Destruction expression
- Camera
- Technical stability
You do not need to aim for realistic structural analysis.
Prioritize destruction that feels good as a game, is easy to understand, and has a realistic processing load.
## Subagent C: Visual / UX / QA Critic
Responsibilities:
- Art direction
- Voxel-leaning city expression
- UI/HUD
- VFX
- Lighting
- Color and screen composition
- Legibility
- Quality assessment via screenshots
- Strict, third-party-perspective self-review
Judge by actually looking at the screen, not "it's good because it was implemented."
The parent agent must not adopt the three agents' opinions as-is; resolve contradictions and make the final decision.
You may have each sub-agent re-investigate or re-evaluate as needed.
# 1. Game concept
Make a game in which you control a giant cat and rampage through a city with skyscrapers.
Direction:
- Giant cat vs. city
- Make building destruction by cat punches the main attraction
- Buildings collapse in a somewhat physical way
- But do not aim for realism
- The city and buildings are somewhat voxelized/simplified
- Prioritize making mass destruction visually easy to understand
- The cat's enormity should be conveyed at a glance
- It should feel good just to control the cat
Place particular emphasis on the quality of the cat model and the cat punch.
As far as possible, carefully craft the cat's model, poses, punch motion, and the reaction on contact.
Implementations that call a simple box "a cat" are not acceptable.
Rather than relying entirely on ready-made assets, build a concise model that fits this game.
# 2. Most important: make it a "game"
The most common failure in this project is being satisfied once you have implemented:
"the cat can walk"
"buildings break"
"the physics runs"
That is prohibited.
At minimum, consider the following and make it hold up as a game.
- A clear start and end
- A goal the player can understand
- A score or achievement metric
- Meaning to breaking buildings
- Meaning to using different cat punches
- Rewards for combos or continuous destruction
- Some constraint such as risk / time / enemies / resources
- Room for the player to improve
- A difference between good play and bad play
- Strong feedback on large-scale destruction
- A mechanism that makes players want to replay
It does not need to be a complex game.
Rather, prioritize that "even a single play of a few minutes makes it clear what to do, the destruction feels good, and you want to do it again."
As initial ideas,
"how much of the city you can destroy within a time limit,"
"the multiplier rises with continuous destruction,"
"large buildings and special facilities are worth high points,"
"think about a destruction route without breaking your combo,"
are candidates, but you do not need to adopt them as-is.
Subagent A and the parent agent should decide the game loop before implementation.
# 3. Technical stack
Required:
- Three.js
For things other than Three.js, you may introduce any widely used, well-maintained library.
A physics engine may also be used.
Example candidates:
- Rapier
- cannon-es
However, you are not bound to these candidates.
Decide the technical choices based on:
- Stable in the browser
- Integration with Three.js
- Performance
- Ease of maintenance
Avoid excessive custom physics-engine implementation.
# 4. Building destruction
Full real-time structural analysis is unnecessary.
Design "plausible-looking destruction" suited to a game.
For example, consider:
- Compose buildings from multiple blocks
- Obtain the contact point, direction, and power of the cat punch
- Lose support above a certain impact
- The upper part tilts
- Part of it separates
- It collapses in a chain
- Separate large rubble from small decorative fragments
- Simplify physics at long distances
However, avoid a design that attaches a rigid body to every one of a huge number of small voxels and destroys performance.
Balance "being physically convincing" with "being able to destroy en masse."
Also avoid lazy implementations where the collapse direction is unrelated to the cat punch, buildings simply vanish, or they collapse the same way every time.
# 5. Cat punch
The cat punch is the center of this game.
At minimum, consider:
- A wind-up before the attack
- The arm swing
- Contact detection
- Contact direction
- Power
- The building's reaction
- Camera reaction
- VFX
- A structure that can use sound effects
- Hit-stop or a similar impact feel
The moment the punch touches a building and the moment the building breaks must visually coincide.
A mere click that destroys a building is insufficient.
Also value control responsiveness.
# 6. Visuals
Do not aim for photorealism.
Direction:
- Stylized
- Voxel / Blocky
- The giant cat's silhouette is easy to read
- The buildings look densely clustered
- Where you destroyed is obvious at a glance
- A large difference before and after destruction
- It feels like the city continues into the distance
- Strong gaze guidance on punches
If necessary, use:
- InstancedMesh
- LOD
- Simplified distant views
- Fake windows
- Decal-like expression
- Particles
Prioritize a unified art style.
# 7. Camera
Design a camera that makes the giant cat and the city destruction look as satisfying as possible.
Do not commit to just a simple fixed third-person camera; also consider camera expression for:
- Normal movement
- Punches
- Large-scale collapse
- Combos
- Special destruction
However, do not harm controllability with violent shaking.
# 8. First, create a fixed evaluation standard
Before starting implementation, the parent agent plus the three sub-agents should create a 100-point evaluation standard.
It must total exactly 100 points.
Include, for example, the following viewpoints:
- Fun as a game
- Fun of controlling the cat
- Satisfaction of the cat punch
- Building destruction/collapse
- Game loop
- Feedback
- Visuals
- UI/UX
- Performance
- Stability
- Level of completion
However, decide the point allocation yourselves.
Important:
Once the scoring standard, point allocation, and each item's judgment conditions are fixed, you must never change them afterward.
Midway changes such as
"this item is hard so lower its points"
"change the standard to emphasize features we could implement"
are prohibited.
Save it as rubric.md or similar, and use the same one in all subsequent evaluations.
For each score band, specify as concretely as possible what must be confirmed to earn what score.
# 9. Develop -> verify -> score -> improve loop
After the first playable version is complete, perform at least 5 and at most 10 improvement iterations.
Iteration 1
->
Run
->
Verify the actual screen
->
Obtain evidence such as screenshots
->
Self-score with the fixed rubric
->
Analyze problems
->
Improve
Repeat this.
At least 5 times is mandatory.
Even if you exceed 80 points in fewer than 5 iterations, ending is prohibited.
From the 5th onward, you may end if
"the overall score by the fixed rubric exceeds 80 points."
If it is 80 or below, proceed to the next improvement.
However, if you reach the 10th, you may end there regardless of the score.
Therefore the end conditions are:
iteration >= 5
AND
score > 80
or
iteration == 10
Make the condition "exceeds 80," i.e., 81 or more, not "80 or more."
# 10. Prohibitions on self-evaluation
Score-rigging is prohibited.
Evaluations like "last time was 72 so this time let's make it 82" are prohibited.
Always base it on results you actually confirmed.
For each iteration, record:
- What you confirmed
- Which evidence it is based on
- Which rubric conditions were met
- Why that score
- What improved from last time
- What is still lacking
For items that cannot be confirmed by screenshots alone, use other evidence such as run logs, FPS, code, and test results.
Do not give high scores to items you have not confirmed.
Adding points by guesswork is prohibited.
# 11. Visual verification
In each iteration, actually launch the game and verify the screen by whatever means possible.
At minimum, confirm:
- Normal play
- The sense of scale between cat and buildings
- Before a punch
- Punch hit
- During building collapse
- After mass destruction
- UI/HUD
Take multiple screenshots as needed.
Have Subagent C critically review the screenshots.
Do not treat visual quality as passing based only on "it should be so in the code."
# 12. No E2E
E2E testing is prohibited.
You must not set up or run an E2E test suite using Playwright, Cypress, or the like.
However, the following are allowed:
- unit test
- integration test
- type checking
- build
- lint
- CPU tests of physics logic
- numerical verification
- actually launching the game and having a human or agent look at the screen
- taking screenshots
- checking state via browser dev tools, etc.
Do not escape into automated E2E testing; evaluate the actual screen.
# 13. Improvement priorities
In each iteration, rather than simply fixing bugs, fix based on
"what to fix next that most improves the actual player experience."
Do not consume iterations on minor code beautification.
The priority is in principle:
1. Problems where it does not hold up as a game
2. The feel of controls, cat punch, and destruction
3. Feedback to the player
4. Visual problems
5. Performance and stability
6. Minor polish
However, fatal bugs are the top priority.
# 14. Performance
Design it to run realistically as a browser game.
Focus on verifying the moments of mass destruction.
Use as needed:
- object pooling
- instancing
- sleeping
- debris lifetime
- physics activation range
- simplified colliders
- fixed timestep
Just because thousands are visible on screen does not mean all thousands need constant high-precision physics.
# 15. Judgment during development
The parent agent should judge not as a mere task manager but as a director who actually makes the game better.
When the sub-agents' opinions differ, choose "the plan that most improves the player experience."
You may cut features whose effect is thin relative to implementation cost.
Conversely, do not reject a small improvement essential to gameplay merely because "it is not written in the spec."
# 16. Deliverables
Ultimately, leave the following:
- A working game
- README
- Controls
- Technical composition
- Explanation of the game rules
- The fixed 100-point rubric
- Each iteration's evaluation record
- Each iteration's score
- Evaluation rationale
- Main improvements
- Final score
- Remaining issues
In the final report, do not end with just "it's complete"; concisely summarize:
1. What kind of game it ultimately became
2. What is fun about it as a game
3. How you implemented the cat punch and building destruction
4. What you used the three sub-agents for
5. The fixed rubric
6. The score progression from iteration 1 to the final iteration
7. What you actually confirmed in each iteration
8. The weaknesses that ultimately remain
# 17. Re-confirming the most important constraints
The following are absolute conditions.
- Parent: GPT-6 Luna Max
- Use three Luna Max sub-agents as much as possible
- Three.js-centered
- A giant cat destroys a cluster of skyscrapers
- Build the cat model properly
- Build the cat punch properly
- Handle building collapse somewhat physically
- Voxel/Stylized-leaning rather than photoreal
- Make it a game, not a tech demo
- Fix a 100-point rubric before implementation
- No changing the rubric afterward
- No E2E
- Self-evaluate based on evidence such as the actual screen and screenshots
- No adding points by guesswork for unconfirmed items
- At least 5 improvement iterations
- At most 10
- From the 5th on, you may end at 81 or more
- Below 80, continue
- If you reach 10, end
- The point is not to raise the score itself but to raise the actual quality
Before you start writing code, finalize:
"the game loop plan"
"the technical design"
"the three sub-agents' responsibilities"
"the fixed 100-point rubric"
After that, without asking me for confirmation more than necessary, proceed autonomously with implementation, verification, and improvement all the way to the end.