The Game Designer

Design a whole game — rooms, enemies, rules, look and player — and play it in the real engine, with no reload and no export step. Paint tiles with the left mouse button, erase with the right, drop in a Spawn and a couple of enemies, and hit ▶ Play. Everything else is one click away:

The board at the top is your game at a glance — one card per piece a game needs (World, Player, Entities, Start & Ending, Rules, Look, Game), each showing live status, warning when something essential is missing, and jumping you straight to the panel that edits it.
The left dock has five tabbed sections — 🧱 Build, ⛹ Player, 📜 Rules, 🎨 Look and 🏷 Game — while the screens, inspector and Play live on the right.
Everything you place is a tile (part of the fixed world) or an entity (a spawn point, an enemy, a coin). Play converts your rooms into the engine's World and boots a live game over it: guardians and crumbled floors reset every time you enter a room; collected coins stay collected across the whole world.
Pick the Select tool and click any entity to tune it in the inspector.

Scenery: twenty-eight kinds of set dressing now — grass to gravestones, crates, barrels, lanterns, cobwebs, statues, icicles, crystal shards, and the furniture van's latest delivery: a Sofa (two halves, both armrests) and a Lamppost (guttering head over trimmed post) — and STAMPS: one-click grouped pieces (a whole tree, a hedgerow, a graveyard, cellar clutter, a ruin, a wayside camp, the Sofa, the Lamppost) that paint only over empty and scenery cells, never your walls.
And when the engine doesn't stock it, PAINT it — at any size: the Design panel's 🖌 Paint a decoration opens a blank pixel easel from one cell up to 4×3 cells (32×24 pixels), sixteen colours, an eraser, live on the map as you paint. One cell joins the palette as a tile; bigger pieces become your own one-click stamp — a proper sofa, a market cart, a whole shopfront — with a physics choice for the piece (pure scenery, SOLID furniture you can stand on, or a jump-through platform). Painted decorations travel in the export like every custom design.
The easel is always one click away — that's the point of cloning: every cloned tile and pickup carries 🖌 Open in easel, which freezes its look into pixels you own and opens the easel on it (recolouring keeps the living original; rasterising makes every pixel yours — the behaviour and physics ride along untouched). Clone a game, pick any of its designs from the dropdown, hit Edit, and repaint it. Clone → easel → yours.
Tiles: brick and a whole masons' catalogue of walls — stone, rough rock, sandstone, wood, riveted metal and hedge (the maze wall — perfect top-down), each solid, each its own material — plus jump-through platforms, spikes, ladders, conveyor belts, crumbling floor, ice, springboards, lava, and the bouncy Shroom.
Markers: the Spawn (one per world — placing it again moves it) and the Exit, the level ender. Give the Exit a needs collected count and it stays barred, blinking its lock, until you've earned it.
Enemies: the Patroller, Chaser, Turret, the bounding Hopper, the ricocheting Bouncer — and the Flyer, which owns a lane of sky: gliding it, riding a wave along it, or swooping at you when you stray underneath. Arm it from the inspector and it fires too — aimed guns, gravity bombs dropped when you pass below, or both at once. And now the bestiary of yore, straight from the machines that raised us: the Wraith (the Gauntlet ghost — walls mean nothing, it simply comes), the Bat (asleep on the ceiling, decor until you walk beneath — then it shivers, dives, and never sleeps again), the Riser (buried and unhittable until you walk near; the earth churns, a body hauls itself out and shambles — you can't stab soil), the Spider (legs flurry, it drops on a silk thread, dangles, reels back up — the thread is theatre), the Mimic (draws as any collectible you pick, but it never twinkles — that's the tell; come close and the treasure sprouts teeth), and the Crawler (spikes on every side, walking floor, wall and ceiling alike, forever tracing the outline of whatever you place it on). Every one telegraphs before it bites — the reading is the game.
Hazards: the Piston (a press that slams from any wall on a cycle you learn), the Crusher (floor and ceiling jaws — pass between bites), the Steam vent (deadly only while it hisses), and three from the old country: the Pendulum (a bladed bob on a rope — cross on the beat), the Dripper (watch the drop form; that's the warning), and the Dart trap (Manic Miner's poison arrow — rest, warn, whoosh). Three more joined from the same old country: the Sporecap (a mushroom that swells — leave — then bursts a fountain of drifting spores that cannot be killed, only avoided; point it down and it hangs from the ceiling), the Snapper (the plant in the pit — leaf-tips rustle, then it rises to bite; it politely refuses to erupt while you stand on its hole), and the Boulder (Boulder Dash's legacy: deadly on the way down, furniture at rest — perch one over a crumble tile and you've built a trap).
Collectibles all twinkle — a little glint winks over anything that can be taken, phase-offset so rows shimmer in sequence. Scenery never twinkles; that contrast is how the player's eye learns what's a prize and what's a plant, without being told. They count toward completion and score points — and each carries a Grants dial: a coin can also mend a shell point, shield the body for six seconds, gift an extra life, quicken the feet, lift the jump, or freeze every foe — engine-applied the moment it's taken. Collectibles — Coin, Trinket and Key now joined by the Ring, Goblet, Scroll, Crystal, Gold bar, Cherries, Idol and Orb, each with its own look and worth; a tag on any of them is something gates can demand. Every pickup takes a Size × dial (×1/×2/×3 — same pixel art, bigger chunks). Power-ups act the moment you touch them and never count toward the goal — a whole shelf of them: the Drink (a life), Meat (clock time), the Star (invincibility), Shield, Boots (speed), Wings (higher jumps), Energy cell, Hourglass, Moneybag, Snowflake (freezes every enemy), Ammo crate (rapid fire) and the Bomb (clears the room) — plus the two stocked powers: the Power capsule (a shield for a configurable number of seconds) and the Power bomb, which banks up to the Player panel's pocket limit and waits for C. Hover any of them in the palette for exactly what it does.
Every enemy also carries its Death style — when it falls, the engine plays a departure animation (a puff of smoke by default; debris, a cartoon pop, an electrical end, a rising spirit, a quiet twinkle by choice). Nothing vanishes silently in a designed game.
Every entity carries its own settings — a patroller's speed and range, a turret's aim and fire rate — in the inspector, and now its physics too: body size on everything, gravity on chasers, hoppers and bouncers, slam speed and girth on the machines. The Design panel clones any tile, pickup, enemy or hazard so you can rename, recolour and re-default it — a cloned bat still dives; you're naming a variant (the Cave Bat, the Slow Wraith) and making it yours. Cloned pickups get the full look wardrobe — all twenty-two shapes the engine draws, from rings to bombs — while the effect rides the ancestry untouched. And the inspector has the other half: Clone to palette copies a placed entity with the numbers you tuned as the new entry's defaults — tune the perfect variant once, then paint twenty. Custom designs live in the palette and travel inside the export.

The tabs above the grid hold rooms; the Exits row joins them edge to edge. A door edge glows green, and walking off it flicks the screen to the next room, The Manor style.
Two-way wires the return exit back at you automatically; untick it for one-way drops.
The World row decides what your exits are: Flick screens is the Jet Set Willy flip; the Scroller views stitch the same rooms into one continuous level — camera following the player, forced (→ or ↑, with a speed dial), where being scrolled into a wall is a crush, or shmup flight, the forced scroller where you fly — no gravity, whatever the physics preset says, and fire shoots.
Shmup — waves attack doesn't scroll at all: the start room is the arena and every other room is a wave formation flying in from the right, each with a flown, animated entry pattern — the Room panel shows every enemy's actual flight path. Wave rooms wear a 🌊 on their tab; in the shmup views, fire shoots.
Same rooms, same doors — the mode is one dropdown and it travels in the export. → The scroller tutorial

Pick a character from the animated preview strip — fifty-three of them: Willy to Knight, Ninja, Ghost, Ship, Queen, the action pantheon, the C64 heroes' row — the Dragon (flying kick and all), Karateka, the Agent (somersault tuck), Mole, Digger (he blinks while he waits), the arm-cannoned Gunner, Punk Sister, Archer, the Spy, the Egg with boxing gloves, Paper Kid, Skater, Dino, the Bellringer, Gremlin and rotor-spinning Prop-Head — Dash, the fully frame-drawn one, who walks, sprints, brakes on his heels and flips with his own pixels for every stance — and Myrtle the Turtle, who FIGHTS: pick her physics preset and the fire key kicks, spins (in her shell, naturally) and roars, all data, no code. They all share the full pose vocabulary now: walking, running, skidding to a stop, the turn — derived from real momentum, so characters move like they mean it.
Pick the feel: the Movement Lab profiles — Giana, Jet Set Willy, Bruce Lee, Turrican, Robin of the Wood, Wizball, the ball that never stops bouncing (hold jump through a landing to bounce high, release to simmer), and Myrtle, the first preset that carries a whole moveset: pick her and the fire key kicks, spins and roars, landing on enemies stomps them, kills score — combat as data, no code, live in your game the moment you press Play. Three more fighting schools join her: the Brawler (punch, flying kick, stomp — the Chan preset), the Juggernaut (a telegraphed shoulder charge, a slam that clears the room, a stomp that lands like furniture), and the Shadow (wall-jumps and a blade: a lightning strike, an airborne whirl on a cooldown) — as one-click presets, with every physics number editable on top (touch anything and it becomes Custom), plus a lives counter. Set lives to 0 for endless respawns while you're still building.
Pick how dying looks — five death styles (debris burst, tumble off screen, rising ghost, electrocution, pop) — and keep the dust: landings puff, jumps kick off, hard running trails, with every character.
Beyond lives: Energy gives the body hits-per-life (a drained ⚡ bar point instead of instant death — Energy cells refill it), and Fire mode decides how the gun answers the trigger in the shooting views: auto spray, three-round bursts, or one per press.
The down-stances: every grounded body now answers ↓ — once to crouch (slower, two-thirds height), again to crawl (a quarter speed, ONE TILE tall: crawling bodies fit through one-tile gaps and stay down until there's headroom to rise). ↑ or jump rises a stage; ladders outrank stances. The Player panel's Crouch & crawl toggle refuses the whole system per game, and every roster character squashes down convincingly with no extra art.
The stocked Player Powers — all toggleable here: Power bomb pickups bank (up to the Bomb pockets dial — three, by the classics) instead of firing on touch, and pressing C spends one: every killable enemy in the room dies at once, machines survive, kills score. Power capsules shield the body for a configurable number of seconds. The Power bombs (C) toggle turns the ledger off wholesale. Hoard or panic — that decision is the design.
P pauses — every designed game, mid-frame, under a PAUSED card; the same key resumes. And while paused, N steps exactly one tick — frame-by-frame play.
🐞 Debug mode — the engine's X-ray, one button in the play bar: collision boxes on every body (green you, red mobs, grey machinery, yellow items), flag markers on special tiles (hazard red, platform cyan, ladder green…), and a live readout of pose, stance, velocity, energy, powers and the room. It reads and never writes, so it cannot change a run — and with P + N it becomes a frame-by-frame microscope. Games can wear it too: add ?debug to Myrtle's address and watch the pond's machinery think.
Look and feel are independent — a Ghost with wall-jump physics is nobody's business but yours.
Spawn and Exit live beside the Tool buttons now (Select · Erase · Markers) — the two things you place while thinking about layout, always one click away.
The Robin of the Wood preset goes top-down: 8-way running, no gravity, exits in all four directions. Build mazes and forests, not mountains.
The Character Painter: paint your own character pixel by pixel on two frames, and the engine animates the walk, the climb and the jump for you. Painted characters join the roster, play as the player, and can be hung on any enemy as a skin from its inspector — paint a ghoul, dress a Patroller in it.

🏷 Game names your game, writes its story line (shown on the splash screen every designed game now opens with — title, author, story, controls, blinking prompt) and its endings: the win message becomes a full endgame screen, shown after the victory lap — on completion your character celebrates (stars, self-hopping) for a couple of seconds before the announcement, engine-standard. Both endings — victory AND the proper Game Over card — now carry the run's statistics, engine-counted: score, collected, kills, rooms seen, deaths, bombs spent, time. How far you got, and what it cost.
Every event speaks: collects float their points ("+100"), kills cry "POW!", opening gates say "OPEN!", barred exits say "LOCKED" — the engine's Bubbles layer, on automatically in every designed game, drawn in the engine's own 3×5 pixel font.
Every death plays: felled enemies depart visibly (the Outcomes layer) in the style their Death style dial picks — smoke, debris, cartoon pop, electrocution, a rising spirit, a quiet twinkle, or the tight arcade flash.
📜 Rules holds the clock, the points table, and a goals list that gates and exits can demand — collect-all, collect N, reach a room, survive, or hit the exit (the run's ending anyway when an Exit is placed; the goal puts it on the HUD scoreboard and pays its bonus).
🎨 Look is a full Backdrop Editor — start from one of twelve presets (day, dusk, night, forest, space, sunset, ocean, desert, peaks, metropolis, alien, winter), then own the layer stack: sky bands, stars, moon, sun, clouds, hills, snow-capped mountains, forest treelines, rolling sea, skylines, cities with lit windows, a ringed planet, drifting mist — each with its own dials and parallax, over a live panning preview drawn by the real engine.
✨ The Effects layer — the engine's consolidated effects system, dialled at every grain: Ambience is in-room weather (drifting stars, fireflies, rain, snow, rising embers, dust motes, sliding mist — and the STORM: rain with deterministic lightning, the whole room flashing white as a jagged bolt hangs and cools; dry lightning comes alone, and is the eeriest kind — all deterministic, drawn over the tiles, under the actors) with a world default here in Look and a per-room override in every Room panel (kind, density, wind — a starry summit and a misty cellar in the same game). The attached effects make states visible: a pulsing shield aura that blinks through its final second, speed trails, jump shimmer. The bursts mark moments: a collect sparkle, a gate shimmer, the Power bomb's expanding ring. Every one of those wires has its own switch in 🏷 Game — all default ON, each refusable alone. And every pickup takes a per-instance Glow halo dial: twinkle says takeable, glow says special.
Look also decides where each HUD readout sits.

Under the game's title in 🏷 Game: browser saves, a rolling autosave every half-minute, real .json file download/open, and Export/Import.
⎘ Clone a game: the site's own games, converted into real Designer worlds — all sixteen screens of Myrtle the Turtle (her feel, her moveset, her eggs, her sporecaps) or the six rooms of Dreams of Giana land on the workbench as ordinary Designer data, every tile, creature and number yours to edit. The best head-start isn't a blank grid or even a starter yard — it's a whole game you already love, opened up.
Export is your whole game as JSON — every room's tiles, exits and entities with their tuned properties inline, the rules, the look, the painted characters and the player block. Paste it into Import (or into your own code) and it loads straight back; old single-room exports import fine too.
🌐 Publish puts the game on the site's public Arcade shelf — its own play link, a thumbnail drawn from its starting room, and a play counter. Anyone who plays it can press Stop and remix it in the Designer. Sign in first and the publish is yours: the button becomes Update shelf copy on later publishes — same link, plays kept — and you can retire it; guests publish anonymously, frozen forever. Set the title and author in 🏷 Game first (a signed blank byline defaults to your account name).
That round-trip is the whole point: a Retro-64 level is data, not code — drawn by hand, generated by a script, or (the direction this is heading) stored in a collection and edited in the CMS like any other content. → The Build Log

⚔️ Play the Danger Room

📖 Learn the tile format