🖥️ PC2011Re-LogicVERY HARDTerraria rebuild deck
VERY HARD
You get a diggable, buildable world in a weekend and then need five thousand items ordered so that each one gets a moment where it is the best thing you own.
You will get a good prototype. The product is what comes after.
Argue the pass order out before any code is written. Agents generate terrain, then place caves, then place ore as three independent features, and the result looks composited rather than excavated — you can feel the difference within thirty seconds of digging. Watch the storage too: the first draft will be an array of tile objects and the world will end up four hundred tiles wide because that is all the browser can carry. The loop lands in a weekend; the five thousand items and the order in which you meet them are the decade that followed.
- Difficulty
- VERY HARD · 4 of 5
- First playable
- A project
- The original
- 2 team-years
- Released
- 2011 · PC
- Genre
- Sandbox Adventure
Build a 2D tile sandbox: one generated world with surface, caves and an underworld, plus mining, building, crafting and one boss. Canvas 2D, single page. Requirements: - World generation is an ordered stack of passes over one shared tile array, and the order is the design. Surface heightmap, stone blending by depth, caves by worm walkers plus noise, ore veins weighted per depth band, water settling, then a cleanup pass removing floating single tiles. Each pass reads and writes the same array. Generate features independently and composite them and the world reads assembled, not excavated. - That array is a flat Uint16Array of tile ids plus a parallel Uint8Array for walls and light, around 4200 by 1200. Never an array of objects. - Lighting as a queue-based flood fill with a per-tile decrement, recomputed only in a window around the camera. - Player collision resolved one axis at a time, with an automatic step up onto single-tile ledges. - Mining gated by pickaxe power against per-tile hardness. Placement requires an adjacent solid tile or wall, so nothing floats. - Background walls as a separate layer that suppress spawns, which is what makes a base worth building. - Recipes in JSON, gated by proximity to a station. Surface enemies at night only. - One boss summoned by a crafted item, with a pattern unsurvivable without a platform you had to build. Definition of done: a fresh seed gives a world where I can dig from the surface into a cave that was already there, and water tipped in finds a level.
- Five thousand-odd items accumulated across a decade of free updates, ordered so that each one gets a moment where it is the best thing you own
- The bosses, which are the real gates, and the arenas they force you to stop and build before you can fight them
- Hardmode — a world-mutation event that rewrites the map you had already learned
- The tile art and the sound, which is the entire reason a grid of coloured squares reads as an underground
Bitmask autotiling — each tile picks its sprite from its eight-neighbour mask, so edges and corners appear the instant you place a block.
Forty-seven sprites and a lookup table buy you every edge and corner in the game, and the technique is indifferent to what the tiles are: terrain, walls, water, fences, roads, pipe networks, even UI panel borders. It is the cheapest polish available to anything on a grid.
ScopeAn evening— build just this, not the game
Build a bitmask autotiler as a single self-contained HTML file, Canvas 2D, no build step. Requirements: - Generate the tile sheet procedurally into an offscreen canvas at load. No external art: a filled square with its edges and corners drawn darker reads fine. - For each solid tile compute an eight-neighbour bitmask, but only count a corner bit when both of its adjacent edge bits are set. That single rule collapses 256 combinations down to 47 distinct tiles, and skipping it gives visible seams at every diagonal. - Map each valid mask to a sheet index through a lookup table built once at startup. - Paint and erase with the mouse on a 64x40 grid. On an edit reframe only the edited tile and its eight neighbours, never the whole grid. - Hovering a tile shows its raw mask value and resolved index. Definition of done: a painted diagonal has continuous edges with no gaps at the corners, an isolated tile shows the standalone variant, and the hover readout matches what I can see.
Not a clone — Terraria 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.
Abyssal No Reflexes
Terraria, but a puzzle version — same fiction, no reflexes, set in an underwater civilisation. Rendered in blueprint technical drawing.
Build a browser game called "Abyssal No Reflexes". The pitch in one line: a sandbox adventure in the spirit of Terraria, but a puzzle version — same fiction, no reflexes, set in an underwater civilisation. WHAT THIS IS Take the SHAPE of Terraria — 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 puzzle version — same fiction, no reflexes. Keep the world and the tension, remove execution difficulty entirely. Every encounter has a correct answer discoverable by thought. 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 An underwater civilisation. Pressure and oxygen as constant timers, near-total darkness outside a lamp cone, and sound as the main information channel. 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 Blueprint technical drawing. White line-work on a blue ground, dimension lines and callout labels on live objects, and a grid that is diegetic rather than decorative. 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.
- Red Blob Games — making maps with noise functions, the layer you build the passes on top of
- Kenney assets — free CC0 tilesets so you are not blocked on art
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 Terraria to rebuild with an AI agent?
Yes — every game is buildable at some scope. The question is how hard, and Terraria is VERY HARD (4 of 5). You will get a good prototype. The product is what comes after. You get a diggable, buildable world in a weekend and then need five thousand items ordered so that each one gets a moment where it is the best thing you own. Reckon on a project to something you can actually play — not to something that matches the 2 team-years Re-Logic spent.
What makes Terraria hard to rebuild?
You get a diggable, buildable world in a weekend and then need five thousand items ordered so that each one gets a moment where it is the best thing you own. 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 bitmask autotiling — each tile picks its sprite from its eight-neighbour mask, so edges and corners appear the instant you place a block. — an evening of work.
How long does it take to build a Terraria clone?
Wrong question, and it is worth saying why. Nobody rebuilds Terraria — the original took Re-Logic on the order of 2 team-years, released in 2011 on PC. 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 Terraria?
Five thousand-odd items accumulated across a decade of free updates, ordered so that each one gets a moment where it is the best thing you own. The bosses, which are the real gates, and the arenas they force you to stop and build before you can fight them. Hardmode — a world-mutation event that rewrites the map you had already learned. 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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