🃏 Classic1995Klaus TeuberHARDCatan rebuild deck
HARD
Hex geometry is the first wall and it is a solved one, but the game is a trading table — an AI that will not deal turns a negotiation game into a dice game, and the moment you want four humans playing you have bought yourself a server.
You will get the loop working. Then the real work starts.
A project, and the estimate assumes hot-seat only. The hex board is a solved problem — use axial coordinates and it stops being a problem at all. The two real costs are the trading AI and, if you insist on it, online multiplayer, which is a completely separate build with an auth story and a server bill. Do the hot-seat version first and see whether you still want the rest.
- Difficulty
- HARD · 3 of 5
- First playable
- A project
- The original
- 2 team-years
- Released
- 1995 · Classic
- Genre
- Strategy
Build a Catan-style resource trading game, hot-seat for 3-4 players plus AI. Vanilla JS or React, SVG or Canvas board. Rename everything. Requirements: - 19 hex tiles with number tokens, settlements on vertices, roads on edges. Use axial coordinates for the hexes and derive vertex and edge identity from them — do not store the board as pixels, or adjacency will haunt you all weekend. - Standard flow: roll, distribute resources to every settlement touching that number, robber on a seven with discard-over-seven, build roads, settlements, cities and development cards, longest road and largest army, first to ten points. - Longest road is the rule that breaks clones: it is a longest-path search on the road graph that has to handle branching and being cut by an opposing settlement. Write it as a proper graph traversal with tests, not as a running counter. - AI opponents that initiate trades. Each bot holds a private valuation per resource derived from what it is building toward and its production odds, and proposes deals that are good for it and acceptable to you. It must be willing to overpay for the resource it is short of. - Setup phase matters more than anything: placement should be scored by pip count across adjacent numbers and resource diversity, and the AI should place well enough to punish a bad opening. - Show production odds on every tile as pips, and a per-player resource income estimate. The maths is public in the physical game and hiding it helps nobody. Definition of done: longest road correctly transfers when I cut a bot's road with a settlement, and a bot offers me a trade that is good for both of us.
- Trading with people, which is the entire game — bots that trade at fair value are vending machines and bots that never trade make the dice the only mechanic
- The trademarked board, art and name; the mechanics are yours to rebuild, the brand is not
- Real-time multiplayer without a backend, plus everything that comes with one: rooms, reconnects, authoritative state
- The table talk around the robber, which is where half the grudges come from
Placement scored by production odds, shown as you hover
Catan is decided in the first two minutes and most new players cannot see it, because the value of a spot is a sum of dice probabilities across three tiles and nobody does that in their head. Render the expected resource income of every legal placement while the player is choosing, and the opening stops being a coin flip decided by experience. It is the clearest example of a general rule: if the maths is public, hiding it does not create depth, it creates a barrier.
ScopeA weekend— build just this, not the game
Build a hex placement advisor as a single self-contained HTML file. Canvas 2D or SVG, no dependencies. - A field of 19 hexes in axial coordinates, each with a random resource type and a number token from 2 to 12 in the standard distribution. - Derive the vertex and edge sets from the hex grid programmatically. Every vertex knows its adjacent hexes. - On hover over any vertex, compute the expected resources per turn from its adjacent tiles using true dice probabilities, and show the breakdown by resource type. - Shade every vertex on the board by that expected value, so the good spots are visible at a glance without hovering. - Add a diversity weighting toggle: a vertex touching three different resources scores above one touching three of the same at equal pips, and show how the ranking changes when it is on. Definition of done: the top-ranked vertex matches what an experienced player would pick, and turning on diversity weighting changes the top three in a way I can defend.
Not a clone — Catan 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.
Letter of Marque Idle
Catan, but an idle version that plays while you are away, set in the age of pirates. Rendered in black-and-white noir film.
Build a browser game called "Letter of Marque Idle". The pitch in one line: a strategy in the spirit of Catan, but an idle version that plays while you are away, set in the age of pirates. WHAT THIS IS Take the SHAPE of Catan — 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 An idle version that plays while you are away. Offline progress on load, big-number maths from line one, and a prestige reset. The fantasy survives; the input does not. 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 The age of pirates. Wind, cargo and mutiny. The crew is a resource with opinions. 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 Black-and-white noir film. High-contrast monochrome, venetian-blind shadows, film grain, and practical hard lights only. 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.
- boardgame.io — phases, secret hands and hot-seat to online in one model
- colyseus — authoritative rooms when you outgrow hot-seat
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.
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 2 team-years to the counter on the homepage.
Then try these
Questions
How hard is Catan to rebuild with an AI agent?
Yes — every game is buildable at some scope. The question is how hard, and Catan is HARD (3 of 5). You will get the loop working. Then the real work starts. Hex geometry is the first wall and it is a solved one, but the game is a trading table — an AI that will not deal turns a negotiation game into a dice game, and the moment you want four humans playing you have bought yourself a server. Reckon on a project to something you can actually play — not to something that matches the 2 team-years Klaus Teuber spent.
What makes Catan hard to rebuild?
Hex geometry is the first wall and it is a solved one, but the game is a trading table — an AI that will not deal turns a negotiation game into a dice game, and the moment you want four humans playing you have bought yourself a server. That is why it sits at HARD rather than a tier either side of it. If you want the idea without the project, the transferable part is placement scored by production odds, shown as you hover — a weekend of work.
How long does it take to build a Catan clone?
Wrong question, and it is worth saying why. Nobody rebuilds Catan — the original took Klaus Teuber on the order of 2 team-years, released in 1995 on Classic. 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 Catan?
Trading with people, which is the entire game — bots that trade at fair value are vending machines and bots that never trade make the dice the only mechanic. The trademarked board, art and name; the mechanics are yours to rebuild, the brand is not. Real-time multiplayer without a backend, plus everything that comes with one: rooms, reconnects, authoritative state. 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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