Japanese Style Tien-Gow

What It Is

Japanese Style Tien-Gow is a digital adaptation of Datienjiu,
a four-player game played with a 32-tile Tien Gow set.
It may look similar to mahjong at first glance, but the feel is closer to a mix of climbing card games and poker,
where players read the table, infer hidden information, and choose when to commit stronger plays.

We call it “Japanese Style” because it is not intended as a strict reconstruction of one authentic original ruleset.
Part of that is practical: we adopted the ruleset that is actually played in Japan.
We also added structure that feels familiar to Japanese players,
such as East and South rounds made up of four hands each.
Traditional Datienjiu does not always define a fixed ending condition in that way,
so this version organizes the experience into a more game-friendly format.

What We Focused On

• A tutorial and tile-strength guide so new players can learn while playing
• Online multiplayer for up to four players, plus spectator support
• Match structures such as East-only and East-South sessions that make play length easier to follow
• Progression and retention features including achievements, statistics, and titles

Development Notes

The biggest implementation challenge was online multiplayer.
That said, this was not because Datienjiu requires unusual real-time networking.
It is a turn-based game, so the difficulty came more from the standard problems of online implementation in general
than from any genre-specific complexity.

One technically interesting part is the tile data structure.
Each tile is represented by a prime number, and combinations of tiles are represented by composite numbers.
Because of that, a hand of up to eight tiles can be expressed as a single long value,
which keeps combination checks and state handling compact.

The CPU algorithm uses a neural network.
During development, the team played many test matches,
and the history of those actual plays was used as training data.
For a game that is not widely standardized,
learning from repeated in-house play turned out to be a practical way to shape believable CPU behavior.

In terms of production roles, the publisher handled game specifications,
art assets were outsourced, and Arpaggers handled the rest of the development including the Unity implementation.
The goal was not only to present a traditional game,
but to turn it into something that works naturally as a modern digital title.