Duodegen

A practice website for the Duo card game from Crimson Desert by Pearl Abyss. Duo is based on the traditional Korean card game Seotda, played with numbered sticks instead of Hwatu flower cards.

Play against an AI opponent, learn the hand rankings, and sharpen your betting strategy before heading to the Hernand Inn.

Features

• Full Duo card game with AI opponent
• Learning Mode - Real-time strategy advisor with hand strength analysis, pot odds, bluff detection, and opponent card reads (also disables timer)
• Action Feed - Clear log of all betting actions each round
• Hand Name Styles - Switch between Crimson Desert names and traditional Seotda names
• Hand Guide - In-game reference for all rankings and special hands
• Settings - Configurable learning mode and hand name preferences (persisted)

Getting Started

npm install
npm run dev

Open http://localhost:3000 in your browser.

Scripts

Command	Description
npm run dev	Start dev server (Turbopack)
npm run build	Production build
npm run lint	ESLint
npm run type-check	TypeScript check (tsc --noEmit)
npm test	Run tests with coverage (80% threshold)
npm run test:watch	Run tests in watch mode

Game Rules

Deck

20 numbered sticks: 1-10, each in Red and Yellow.

Gameplay

1. Buy in with 15 Silver (Hernand Inn)
2. Each player posts a 1 Silver ante at the start of each hand
3. Each player is dealt 2 sticks
4. You can see one of your opponent's sticks
5. Single betting round: Check, Call, Half Raise, Double Raise, All In, or Fold
6. 10-second timer per decision (auto-Call on expiry)
7. Highest hand wins the pot (minimum pot is 2 Silver from antes)
8. Winner gets first turn next round

Hand Rankings (Best to Worst)

Crimson Desert names shown. Traditional Seotda names available in Settings.

Rank	Hand	Cards
1	Prime Pair	Red 3 + Red 8
2	Superior Pair	Red 1 + Red 8, or Red 1 + Red 3
3	Ten Pair	10 + 10
4-12	Pair	9-9 down to 1-1
13	One-Two	1 + 2
14	One-Four	1 + 4
15	One-Nine	1 + 9
16	One-Ten	1 + 10
17	Four-Ten	4 + 10
18	Four-Six	4 + 6
19	Perfect Nine	Sum ends in 9
20-26	8-2 Points	Sum ends in 8 down to 2
27	1 Point	Sum ends in 1
28	Zero	Sum ends in 0

Special Hands

Hand	Cards	Ability
Judge	3 + 7	Beats 9-Pair or lower; becomes Zero vs Ten Pair+
Executor	Red 4 + Red 7	Beats Superior Pair; becomes 1 Point otherwise
Warden	4 + 9	Rematch if opponent has One-Two or lower
High Warden	Red 4 + Red 9	Rematch if opponent has 9-Pair or lower

Project Structure

src/
  engine/          # Game logic (no UI dependencies)
    types.ts       # Stick, HandRank, BetState, GameState, ActionLogEntry
    deck.ts        # Create, shuffle, deal
    hand-evaluator.ts  # Evaluate hands, resolve showdowns
    hand-names.ts  # Crimson Desert & Traditional Seotda name sets
    betting.ts     # Available actions, apply bets
    game-state.ts  # Reducer-based state machine
    ai.ts          # AI opponent strategy
    strategy.ts    # Learning mode strategy advisor engine
  components/
    game/          # Game UI (Stick, BettingControls, Timer, ActionFeed, etc.)
    ui/            # Shared primitives (Button, Modal)
    HandGuide.tsx  # In-game hand rankings reference
    SettingsModal.tsx  # Settings for learning mode & hand names
    GitHubCorner.tsx   # GitHub repo link
  hooks/
    useGameState.ts  # Central game hook (useReducer + side effects)
    useTimer.ts      # 10-second countdown
    useLearningMode.ts # Strategy advisor derivation
    useSettings.tsx  # App-wide settings context (localStorage-persisted)
  app/
    layout.tsx     # Root layout (SettingsProvider, GitHubCorner)
    page.tsx       # Landing page
    play/page.tsx  # Game screen
    rules/page.tsx # Full rules reference

Tech Stack

• Next.js 16 (App Router, TypeScript, Turbopack)
• Tailwind CSS v4
• Framer Motion for card animations
• Vitest + Testing Library with v8 coverage (80% threshold)
• GitHub Actions CI (lint, type-check, test, build)