1💣 MinesweeperClear the board without touching a mine, then post your time to the global leaderboard.Under the hood: Flat arrays, safe first click, queue-based opening, chording, global leaderboard 2🐍 Snake StudioClassic snake with food types, enemy snakes and a 3D view.Under the hood: Two clocks, direction queue, food table, enemy AI, 3D view 3🧱 Breakout StudioBounce the ball, smash the bricks, with generated levels.Under the hood: Sub-stepped physics, circle vs polygon, level generator 4🪜 Stairs DownDrop down an endless shaft: land on platforms, avoid the spikes.Under the hood: Sub-steps, moving platforms, jump feel, endless shaft 5♟️ Chess PuzzlesFind the winning move against a real chess engine.Under the hood: Chess engine, search, Web Worker 6📦 Box WorldPush the crates onto the goals (Sokoban), with undo and auto-walk.Under the hood: Grids, undo, BFS auto-walk, dead squares 7🐱 Lucky Cat Rooftop RunA 3D rooftop runner: jump the gaps and keep running.Under the hood: Three.js, chunked tracks, jump buffering 8🎵 Orbit BeatA rhythm game that listens to the music and finds the beat.Under the hood: Audio clock, FFT, beat detection 9🏯 Chinese Chess River & PalaceChinese chess (xiangqi) mate puzzles.Under the hood: Move tables, mate search, puzzle generator 10💡 Lights Out 24Switch the lights off; every press changes its neighbours, now with three states.Under the hood: Linear algebra mod 3, minimum solutions 11🔢 SudokuSudoku with graded difficulty, from gentle to fiendish.Under the hood: Bitmasks, human-technique solver, grading 12⚔️ Three Kingdoms BattleA turn-based battle map with famous generals and a scoring AI.Under the hood: Engine/UI split, seeded maps, AI scoring, phone taps, PWA 13👾 Alien PatrolA light-gun shooter: tap the aliens before they reach you.Under the hood: Light-gun shooter, state machines, hit zones, waves 14🔲 2048Slide the tiles, join the numbers, reach 2048.Under the hood: The shared kit, DOM animation, undo, save/resume 15🐔 Chicken Cross RoadHop forward, dodge the traffic, collect the corn.Under the hood: Seeded endless world, time-based hazards, rival AI, PWA 16🧮 Killer SudokuSudoku where the digits in every dotted cage must also add up to the number shown.Under the hood: Offline generator with uniqueness proof, cage-sum solver, symmetries, cage helper 17👑 Royal RegionsPlace one crown in every row, column and colour region, and never let two crowns touch.Under the hood: Unique-solution generator with counterexample repair, 10 icons, colour palettes 18☀️ Sun and MoonFill the board with two symbols: no three in a row, equal numbers in every line, and obey the = and × clues.Under the hood: Human-style logic solver, greedy clue removal, 8 symbol pairs 19🧵 TrailDraw one path through every square: visit 1, 2, 3… in order and never cross yourself.Under the hood: Shaped boards (masks), Hamiltonian path generator, walls, drag drawing 20🧩 PatchworkCut the board into rectangles. Every patch holds one number, and the number is its size.Under the hood: Shaped boards, exact-cover generator, rectangles by dragging, hints 21🏰 Hex BastionDefend the gate on a hex map with generals and strategists from 三國演義.Under the hood: Hex grid (cube maths), seeded map and waves, generals as towers, bot-tested balance 22⚫ OthelloTrap the other side's discs and flip them. Four computer levels, or two players.Under the hood: Rules engine checked by move counts, negamax + alpha-beta, endgame solver, Web Worker AI 23🔴 Connect 4Drop discs and line up four. Four computer levels, three board sizes.Under the hood: Falling discs, forced moves, transposition table with Zobrist keys, solver check 24⭕ Connect 5Line up five stones (Gomoku). Four computer levels, three board sizes.Under the hood: Scored 5-cell windows, threat detection, tap-twice on phones 25🐷 Flying PigTap to flap the little wing and keep the pig in the air. Dress your pig up.Under the hood: Fixed-timestep physics, circle vs rectangle collision, reachable random gaps, daily seeded run 26🀄 Klotski (華容道)Free the big red block from the crowd. The old Chinese sliding puzzle, with hints.Under the hood: Breadth-first search from the finished board, so every puzzle is solvable and measured 27🏎️ Jet RacerRace 3 laps in four scenes, and jump over the traffic with your jets.Under the hood: Road segments projected to the screen, hill clipping, fixed-timestep physics, jump height vs car height 28🔤 Word GuessGuess the hidden 5, 6, 7 or 8 letter word from green, yellow and grey clues.Under the hood: Two-pass scoring for repeated letters, state rebuilt from the guess list, daily word from a date seed 29🔎 Word SearchFind the hidden words in the grid. Drag across letters in up to 8 directions.Under the hood: Words placed at random with overlap when letters match, uniqueness check, drag snapped to 8 directions 30🕐 Countdown NumbersPick 6 numbers, big or small, and reach the target before the clock runs out.Under the hood: Brute-force solver over every subset, targets that can always be reached, computer solution 31🌭 Sausage Dog WalkWalk your sausage dog round a sunny garden and keep the peace when squirrels and cats appear. Dress the dog up.Under the hood: Raycasting (a ray per column), sprites with a depth buffer, a garden maker, line of sight 32👾 Space InvadersShoot the alien swarm in Classic or New style (tiny aliens), and catch tri-laser, bomb, homing missile and rocket drops.Under the hood: A formation moved by one corner, sub-stepped fast shots, homing steering, erodible bunkers 33🎨 Colour MatchFind the one square that matches the colour on show, in a grid of near-identical shades. 60 seconds, +5 for every find.Under the hood: Colour families in HSL, a unique match by RGB distance, difficulty from a counter 34🚂 Train TracksLay one rail line from the entry to the exit using the row and column counts, then watch a train ride your track.Under the hood: A route grown by bumps, a counting solver that proves one answer, an offline puzzle bank, a train moving along a path 35🎱 PoolPlay 8-ball against the computer, or solve trick shots: bank shots, kick shots, combinations and double pots.Under the hood: A fixed-step physics engine, a shot recorder that judges the rules, a computer player that tries many shots, trick shots found by search 36♟️ DraughtsPlay draughts on a 6x6, 8x8, 10x10 or 12x12 board against the computer or a friend, with classic or flying-king rules.Under the hood: Moves as paths, compulsory captures, rules checked against published move counts, a look-ahead computer player (alpha-beta search) 37🐘 Jungle Chess 斗獸棋The classic animal board game: capture by rank, swim with the rat, jump the river with the lion and tiger, and reach the enemy den.Under the hood: One function for every capture rule, river jumps, traps and dens, a look-ahead computer player (alpha-beta search) 38⛩️ Shogi 将棋Japanese chess: promote pieces, capture and drop them back on the board, and checkmate the king. Play the computer or a friend.Under the hood: A move packed into one integer, drops from a hand, rules proved with perft counts, a look-ahead computer player (alpha-beta search) 39🀄 Banqi 暗棋Dark chess: all 32 pieces start face down. Flip, capture and out-last your opponent. Taiwanese or Hong Kong rules, computer or friend.Under the hood: Hidden information as a second array, a computer that averages over unseen pieces, a cannon that jumps 40🧊 3D Rubik's CubeA cube you can spin and twist in 3D: drag a sticker to turn a layer, scramble, time yourself, 2x2 to 4x4. Includes a beginner solving guide.Under the hood: 3D drawn on a plain 2D canvas (rotation, perspective, painter's algorithm), turns as layer rotations, proved with the cube's known cycle lengths 41⚫ Go 圍棋The classic game of surrounding territory. Boards from 5x5 to 19x19, handicap stones, play the computer or a friend.Under the hood: Groups and liberties by flood fill, repeated positions caught by hashing, a computer that learns from thousands of random games (Monte Carlo tree search) 42🌀 Word SwirlEvery letter belongs to a hidden word, and the words wind around the board in any direction. Trace them all. Short 3 and 4 letter words included.Under the hood: Cutting a grid into snakes with backtracking, making every word unique by counting how it can be traced, a repair step that swaps words 43♞ Chess VariantsNormal chess, or blind chess: hide the pawns, show only pawns, or hide everything. A secret queen disguised as a pawn, Chess960 and a board editor.Under the hood: Reusing a checked chess engine under a variants layer, hidden information as a note beside the real state, two move lists for one piece, blind display rules 44✈️ Aeroplane Chess 飛行棋The classic dice race. Throw a six to take off, jump along your own colour, fly across the shortcut and send rivals back to the hangar. 2 to 4 players.Under the hood: One number per plane, resolving a move into jump and fly stops, a dice turn state machine, a computer from a score table with a danger term 45🔮 波子棋 Chinese CheckersHop your marbles across the star to the opposite corner. Long hops over any piece, chain hops, 2 to 6 players.Under the hood: Hexagonal grids with cube coordinates, long hops, chained hops by breadth-first search, a greedy computer 46🎲 Backgammon (Tawla)The national game of the Middle East: race 15 checkers home, hit the lone ones, try the doubling cube. Also Plakoto (pin game) and Fevga (blocking game).Under the hood: Moves as single dice steps, the use-both-dice rule by search, three rule sets from one engine, a hit-risk evaluation for the computer 47🌰 Mancala (Kalah, Oware, Mangala)Sow the seeds round and capture them. Three games from Ghana to Turkey: Kalah, Oware and Mangala. Play the computer or a friend.Under the hood: One ring of 14 numbers for three rule sets, the last seed deciding captures, a sowing trace replayed on screen, alpha-beta with extra turns 48🏺 Royal Game of UrA 4,500-year-old race game from Mesopotamia: four two-sided dice, seven pieces, rosettes for extra throws, capture on the shared lane.Under the hood: One number per piece on crossing paths, dice as a probability table, expectimax with a transposition table 49🐘 ShatranjChess as played a thousand years ago: a slow Ferz, a leaping Alfil, no castling, and a bare king rule.Under the hood: Board as signed numbers, move tables, alpha-beta search, end rules as a state machine 50⚪ DamaTurkish and Arab draughts: no diagonals, flying kings, and you must always take the biggest capture.Under the hood: A move as a whole turn, depth-first capture chains, the majority rule as a filter, searching through forced captures 51🐍 SenetThe ancient Egyptian game of passing: four throwing sticks, swaps, and the House of Water.Under the hood: A piece as a number on an S-shaped track, a throw as a probability table, swaps, expectimax 52🗺️ ConquestConquer Europe in 1914: dice battles, power blocs for bonus armies, up to six players, drawn soldiers and cannons.Under the hood: Coastline bitmap, nearest-seed territories, exact dice odds, a map painted in layers, a computer player made of a few scores 53🏙️ Food Court EmpireBuy food shops on Tidehaven High Street, collect rent, add shops and bankrupt your rivals. 2 to 5 players, people or computers.Under the hood: Food-business board as data, drawn icons, rent tables, debt and bankruptcy state machine, computer players made of a few rules 54🧟 OutbreakSurvive three zombie cities: shoot the swarm, loot houses, rescue survivors, beat the bosses and uncover who started it.Under the hood: City as tile arrays, a distance map the swarm follows, rules separate from drawing, a story told by events 55🀄 MahjongHong Kong or Taiwan rules against three cute, dramatic animal friends: 上 / 碰 / 槓 / 糊 with bubbles, shouts and tears.Under the hood: Game flow as a state machine, win detection by set splitting, shanten for the computer players, scoring tables as data 56🃏 SolitaireKlondike patience: tap or drag, draw one or three, undo, hints, a daily deal, and deals checked so they can be won.Under the hood: Card game state as plain arrays, move generator, depth-first solver with a seen-set, animation by position maps 57🧩 Mahjong PuzzlesWhich tiles win, which tile to throw, how many faan or tai, and which winning tile scores most, in Hong Kong or Taiwan style.Under the hood: Building a winning hand then spoiling it, answers computed from the real scoring rules, counting unseen tiles, make-test-retry puzzle generation 58✈️ Jet StrikeFly a 3D jet into an asteroid field: shoot rocks that break into pieces, dodge drones, boost, bomb and beat the Dreadnought boss.Under the hood: Perspective projection by hand, flat-shaded triangles, fractal rock meshes, swept collision (no bullet tunnelling), a rules/drawing split tested by bots 59🕊️ FlockA new two-player board game I invented: stones move as far as their flock is big, and you capture by sandwiching. Three rules, four computer levels, or two players.Under the hood: Inventing a game: three rules, rules tuned by computer self-play, alpha-beta search with undo, and a summary of what the older board games taught 60🎲 RunesA new dice-and-magic board game I invented: roll two dice, pick one, and its number casts a spell from chess, shogi, Othello, xiangqi, Senet or Ur. Capture the enemy Mage or hold the Throne.Under the hood: Inventing a game with dice: choosing between two rolls, chance nodes in the search, spells as moves, tuned by self-play 61⚪ MorrisNine Men's Morris, the old mill game: place nine stones, slide them, fly when you are down to three, and take a stone for every three in a row. Four computer levels or two players.Under the hood: A JavaScript rules engine checked against a Python one on 121,831 positions, alpha-beta search with iterative deepening, repeat avoidance 62👻 Haunted MazeA first-person horror game in a huge random Louis XVI mansion: open doors, spot the paranormal by clicking, 20 ghosts that hit you from behind, ghosts coming out of walls, paintings and mirrors, sweets for lives.Under the hood: Rules engine tested by a bot over 4 whole stages; same raycaster method as Chapter 31 63🟦 Block FitPlace three shapes of 2 to 9 cells on a square board (12x12 by default, 6x6 to 20x20) and fill a row or column to clear it. Like Tetris, but nothing falls.Under the hood: A shape maker that always gives exactly the cells asked for, a fair-hand rule, bot-tested rules, drag with a preview of the lines you will clear 64🏹 Arrow MazeA board of long bending arrows: click one and it slides out head first, but only if nothing is in front of its head. Start on the outside and work in. Arrows up to 40 squares, 20x20 by default.Under the hood: A puzzle maker built backwards so every board can be solved, bodies kept near their ring so arrows can be long, bot-tested on 288 boards 65🏴‍☠️ Pirate CannonsTwo cartoon pirate ships trade cannon fire. Drag back to aim, mind the wind, break the enemy's mast and hull, or kill the captain. Both ships get different upgrades each round.Under the hood: Real arcs with wind and drag, blocks that break by energy and fall when cut off, buoyancy that sinks a ship, an enemy captain that simulates its own shots; tested by 120 bot battles 66🛩️ Banner PlaneFly a small plane towing a banner over a random 3D city, day, sunset or night. Take off, land, or load your own 3D city model (.glb or .obj) and fly around it.Under the hood: Real-size flight physics with an easy mode that cannot stall, a rope-and-banner chain, one height map for crashes in both the random city and a loaded model, three.js 3D drawing