Super Auto Pets: The Board Game — Online

A web app for playing the Super Auto Pets board game remotely. 1v1 for now; the engine is built to grow to more players. Play a friend by room code, or play solo against a computer opponent (easy / medium / hard).

Stack

• Backend: Go (stdlib-first). Pure game engine in internal/game, WebSocket sync via coder/websocket, persistence as JSON blobs in SQLite (modernc.org/sqlite, no cgo).
• Frontend: React + Vite + TypeScript in web/. DOM/CSS card rendering and battle animations.
• Tasks: mise (mise.toml).

Quick start

mise run install-web   # once: npm install
mise run serve         # build frontend + server, run on :8080

Open http://localhost:8080, host a game, and join from another browser (or incognito window) with the 5-letter code.

Development

mise run dev           # Go server on :8080 + Vite hot reload on :5173
mise run test          # Go tests (game engine)
mise run check         # go vet + frontend type-check

During development open the Vite URL (http://localhost:5173); it proxies /api (including the WebSocket) to the Go server.

Configuration

Set via environment or a .env file (see .env.example):

Variable	Default	Purpose
DATA_DIR	data	Directory holding the SQLite DB
PORT	8080	HTTP port
STATIC_DIR	web/dist	Built frontend to serve

Rules implemented

Six rounds, each with its own shop tier deck. Per round:

1. Shop — each player has 3 gold and players alternate actions: buy one of 4 face-up cards (1 gold — the only action that costs anything); sell any number of hand cards for free (each becomes an 🍎 apple, +1 power food, and Sell effects fire); or trade in 3 same-suit pets (the Triple action, also free) to pick 1 of the top 2 cards of the next tier's deck — Triple effects fire on the traded cards and the received pet's Buy effect fires. Passing is a final action, only legal at 5 pets or fewer: it forfeits remaining gold and ends that player's shopping for the round. The shop closes once everyone has passed.
2. Arrange — Battle Prep effects fire first (e.g. Giraffe hands out apples), then players secretly order their decks. Food cards apply to the next pet after them; trailing foods are wasted. A pet only benefits from its last-applied perk (e.g. Honey, Garlic).
3. Battle — automatic stack machine. Cards reveal off the top of each deck until a pet is in play. Play effects fire on reveal (rocks roll a d6 with faces 0/0/1/1/2/2 and hit the opposing pet before the clash; Skunk strips foods; Wolverine steals apples; Chili mills the enemy deck). The two pets simultaneously deal their full power to each other as damage markers; a pet with markers ≥ power faints (attack never drops while wounded). Faint effects push summons onto either deck, recycle apples (Dodo), set aside delayed/recurring/conditional rock volleys (Badger, Blowfish, Snake, Crocodile), raise auras (Turkey, Mammoth), or arm a team shield (Turtle). Survivors that took damage fire Hurt effects (Peacock, Camel, Gorilla). Shields (Turtle/Gorilla/Melon) block whole hits, Garlic shaves 1 per attack, and Scorpion KOs anything its clash attack manages to hurt. Hippo heals when enemies faint; Rhino rocks each enemy pet as it's played. A clash that changes nothing ends the battle as a stalemate draw. Last player able to field a pet wins: 1 trophy for rounds 1–5, 2 for round 6. Draws award nothing.

Apples and bees are temporary: they leave your deck after the battle. Most trophies after round 6 wins.

Packs

Three card packs are playable, chosen by the host in the lobby. Each pack is six tiers, one per round, and every pet ships as two copies.

Turtle pack

Tier	Pets	Food
1	Ant, Cricket, Duck, Otter, Mosquito, Fish	—
2	Worm, Flamingo, Peacock, Swan, Rat, Spider	Honey
3	Dog, Dolphin, Giraffe, Camel, Sheep, Dodo, Badger	Garlic
4	Squirrel, Turtle, Rooster, Bison, Blowfish, Skunk, Hippo	Pineapple
5	Monkey, Rhino, Crocodile, Scorpion, Seal, Shark, Turkey	Chili
6	Gorilla, Fly, Leopard, Mammoth, Cat, Snake, Wolverine	Melon

Golden pack

Tier	Pets	Food
1	Groundhog, Pied Tamarin, Chipmunk, Cone Snail, Bulldog, Opossum	—
2	Black-Necked Stilt, Lizard, Hercules Beetle, Stoat, Desert Rain Frog, Honduran White Bat	—
3	Guinea Fowl, Surgeon Fish, Osprey, Anteater, Bear, Royal Flycatcher, Flea	Avocado
4	Saiga Antelope, Vaquita, Poison Dart Frog, Manta Ray, Slug, Cockatoo, Manatee	Potato
5	Nyala, Nurse Shark, Giant Isopod, Blue-Ringed Octopus, Raccoon, Fire Ant, Macaque	Durian
6	Highland Cow, Wildebeest, Grizzly Bear, Catfish, Komodo, Bird of Paradise, German Shepherd	Tomato

The Golden pack adds mechanics the Turtle pack doesn't have:

• Trumpets — an ephemeral battle resource pets earn and spend mid-fight.
• Golden Retriever — once per battle, a side that runs out of cards but still holds Trumpets fields one, its power equal to those Trumpets.
• Avocado — a persistent set-aside token you can discard in place of gold.
• Nurse Shark — on entry it spends every Trumpet it can (up to 3), throwing two rocks at the enemy per Trumpet spent.
• Cockatoo — a shop-time reveal, plus Manta Ray's free first buy, Blue-Ringed Octopus' per-buy apples, and more.

Unicorn pack

Tier	Pets	Food
1	Alchemedes, Cuddle Toad, Pengobble, Barghest, Basilisk, Baku	—
2	Thunderbird, Gargoyle, Frost Wolf, Mothman, Nightcrawler, Bigfoot	Fairy Dust
3	Fur-Bearing Trout, Calygreyhound, Tatzelwurm, Skeleton Dog, Mandrake, Lucky Cat, Slime	Water of Youth
4	Roc, Chimera, Kraken, Unicorn, Abomination, Rootlin, Fairy	Health Potion
5	Kitsune, Pixiu, Red Dragon, Amalgamation, Vampire Bat, Werewolf, Loveland Frogman	Big Mana Potion
6	Sleipnir, Sea Serpent, Bakunawa, Manticore, Team Spirit, Behemoth, Quetzalcoatl	Cornucopia

The Unicorn pack adds two mechanics the others don't have:

• Mana — a persistent resource (unlike ephemeral Trumpets): pets earn it in the shop (Cuddle Toad, Thunderbird, Roc) and in battle (Alchemedes, Fur-Bearing Trout, Kitsune, Tatzelwurm per rock blank), and spend it to power abilities (Pengobble, Gargoyle, Sea Serpent, Bakunawa; Sleipnir's very Power equals your Mana). It carries over between rounds until spent, so you can bank it up.
• Ailments — temporary debuff cards attached to a pet during battle, removed at round end like apples. Spooked lowers the pet's clash attack (−1 each, min 0); Exposed raises the damage it takes per hit (+1 each). They stack, can be added to the enemy pet or dropped on top of the enemy deck (Frost Wolf, Slime, Kraken, Red Dragon). Baku shrugs off the first one it takes, Unicorn turns the next friendly one into apples, and Manticore makes enemy ailments count for more.
• Plus a game-wide discard pile the higher tiers reach into (Chimera, Abomination), pet-recycling (Fairy, Loveland Frogman's bounce), and shop tricks — Bigfoot's deck peek, Water of Youth's upgrade, Quetzalcoatl's reveal.

Layout

cmd/server/          entrypoint
internal/game/       rules engine (pure, fully tested)
internal/ai/         computer opponent (decides from a player View only)
internal/server/     HTTP + WebSocket rooms; drives bot turns
internal/store/      SQLite persistence
internal/env/        .env loading
web/                 React frontend

The computer opponent

Any seat can be a bot (Player.IsBot); humans and bots are interchangeable to the engine, which is what will let future >2-player games mix them freely. The AI in internal/ai never touches the Game — it decides from a game.View, the same per-player state a human client is sent, plus a persisted memory of public observations (battle lineups, the event log, shop row changes). It cannot see your deck order, hidden trade picks, or the shuffled shop decks. It scores candidate moves by Monte-Carlo battle rollouts (game.SimulateBattle) against sampled guesses of your deck and ordering, blended with a long-term deck-value heuristic; difficulty tunes a softmax over the scored moves plus the rollout budget.