Thirteen — Vietnam's national card game

Overview

A mobile reimagining of Tiến Lên, Vietnam's national card game. The country's most popular card game, rebuilt with an interface clear enough for players anywhere to pick up.

Key features

• Single-player AI: matches against AI opponents at a range of difficulties
• Multiplayer: real-time online play for four, built on Photon
• Faithful rules: straights, pairs, bombs and every other Tiến Lên combination
• Intuitive UI: card selection, passing and play animations

Technical challenges

The AI uses Minimax-based hand optimisation, and Photon PUN2 handles real-time turn synchronisation. Supabase stores match statistics and leaderboard data.

// Validating a play
public bool IsValidPlay(List<Card> cards, List<Card> prevPlay) {
    var combo = ComboDetector.Detect(cards);
    if (combo == ComboType.None) return false;
    if (prevPlay.Count == 0) return true;
    return ComboComparer.IsBigger(cards, prevPlay);
}

Rules

• A special ranking that runs 3 → A → 2
• Pairs, triples and four-of-a-kind (bombs) can be played as combinations
• Straights (runs of consecutive ranks) are supported
• A 2 is the strongest single card and can only be beaten by a four-card set