Game review

Caro Board (Gomoku)

7.2 / 10

Developer
Trần Hữu Đạt
Publisher
Trần Hữu Đạt
Released
1 January 2024
Platforms
web
Genre
board,strategy
Monetisation
free
Players
true

The short version

A correctly-implemented five-in-a-row board with a genuine CPU opponent that responds sensibly, confirmed to place stones exactly where tapped on a real touch device - let down slightly by a board that runs about ten CSS pixels wider than a phone's own viewport, requiring a small scroll or pinch to reach its rightmost column.

Biggest strengths

  • Correct Gomoku rules on a full 20x20 board, with both local Player vs Player and Player vs Computer (playable as either X or O)
  • The CPU opponent responds immediately and sensibly, contesting space near the player's move rather than playing randomly - confirmed by watching it place a stone directly adjacent to a real touch-placed move
  • Tap-to-place was confirmed precise: a specific cell was targeted by its exact on-screen position, and the underlying board-state array confirmed the stone landed in that exact cell, both on a simulated phone and via mouse on desktop

Biggest weaknesses

  • The board's own CSS renders about 10 logical pixels wider than a 390px-wide phone viewport, so the rightmost sliver of the 20-column grid sits just off-screen and needs a small scroll or pinch-zoom to reach - a minor but real mobile-fit rough edge on an otherwise fully working touch board
  • No visible move counter, undo, or difficulty setting for the computer opponent
  • Presentation is functional and minimal - flat colours, no sound effects, no animation on placement

Who it's for: Fans of Gomoku/Caro (Vietnamese five-in-a-row) who want a simple, dependable implementation with a real opponent.

Our recommendation: play

7.2 / 10

Opening

Caro Board is Gomoku — five in a row wins, played here on a proper 20x20 grid rather than a cramped smaller board — with both local two-player and a genuine CPU opponent to play against. It's a single-file implementation with no dependencies, and it gets the fundamentals right.

Controls, confirmed precisely

Tap-to-place accuracy was tested directly rather than assumed: a specific cell was targeted using its exact on-screen bounding box, and the game's own boardState array was read afterward to confirm the stone landed in precisely that cell — both with a real touch tap on a simulated phone and a mouse click on desktop. In Player vs Computer mode, the CPU responded within a fraction of a second with a sensible move placed directly adjacent to the human's stone, rather than playing randomly, which makes it a genuinely useful practice opponent rather than a token AI.

The one real rough edge

Testing also turned up a small but real mobile-fit issue: the board's own CSS renders roughly ten logical pixels wider than a typical 390px phone viewport, so the last sliver of the twentieth column sits just past the right edge of the screen and needs a short scroll or a pinch-zoom-out to reach. It doesn't block play — every cell that matters for most games (which tend to cluster around the centre) is reachable without any extra effort, and the fix for a player who does need that far column is trivial. But it's worth knowing before diving in on a smaller phone.

Presentation

It's intentionally plain: a dark background, pink-accented X and white O markers, and grid lines that stay legible even on a busy late-game board. There's no sound and no placement animation, which keeps the focus squarely on the board itself.

Final Verdict

A correctly-built Gomoku implementation with a real, responsive CPU opponent and touch placement confirmed to be pixel-accurate. The board's slight viewport overflow is a genuine but minor flaw rather than a dealbreaker. Recommended for Gomoku fans looking for a dependable version of the classic.

Pros and cons

Pros

  • Correct Gomoku rules on a full 20x20 board, with both local Player vs Player and Player vs Computer (playable as either X or O)
  • The CPU opponent responds immediately and sensibly, contesting space near the player's move rather than playing randomly - confirmed by watching it place a stone directly adjacent to a real touch-placed move
  • Tap-to-place was confirmed precise: a specific cell was targeted by its exact on-screen position, and the underlying board-state array confirmed the stone landed in that exact cell, both on a simulated phone and via mouse on desktop
  • Clean MIT licence, no analytics, zero console or page errors on either platform

Cons

  • The board's own CSS renders about 10 logical pixels wider than a 390px-wide phone viewport, so the rightmost sliver of the 20-column grid sits just off-screen and needs a small scroll or pinch-zoom to reach - a minor but real mobile-fit rough edge on an otherwise fully working touch board
  • No visible move counter, undo, or difficulty setting for the computer opponent
  • Presentation is functional and minimal - flat colours, no sound effects, no animation on placement

Category scores

Category scores are the reviewer's read on each area. They inform the overall score but do not average into it — the number at the top of the page is a judgement, not a calculation.

  • Gameplay 7 / 10
  • Visuals 6.5 / 10
  • Sound 4 / 10
  • Originality 5.5 / 10
  • Replayability 7 / 10
  • Controls 7 / 10