STARBOX

BOARD · ORIGINAL BROWSER GAME

Connect Four

Drop pieces into five columns and form a line of four before the computer.

Implementation reviewed August 11, 2026 · Published independently by Starbox

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DIRECT ANSWER

How does Connect Four work on Starbox?

Choose one of five columns to drop a pink piece into the lowest empty cell. Make four horizontally, vertically or diagonally before the computer does.

  • Board: 5 columns by 4 rows
  • You play pink and move first
  • A full column rejects another piece

Rules and objective

Drop pieces into five columns and form a line of four before the computer. Pieces occupy the lowest available row and the board checks horizontal, vertical and diagonal sequences after each turn.

How scoring works

A player line records a 100-point win. Scores are saved only in this browser's local storage, so changing devices or clearing site data starts a new local record.

What we checked in this build

We tested full columns, player wins, computer responses, restart behavior and representative diagonal lines.

This note describes the Starbox implementation rather than the rules of every similarly named game elsewhere.

FIRST-HAND CHECK

Test record

Tested
August 11, 2026
Environment
Source-level board and win-path review plus production build on Windows 11.

Procedure

  1. Traced bottom-up placement and the full-column guard.
  2. Reviewed horizontal, vertical, and representative diagonal win paths with computer replies.
  3. Checked the post-win guard and New game reset.

Observed result

Pieces occupied the lowest empty cell, a full column rejected further input, wins stopped the round, and New game cleared all 20 cells and restored the opening message.

WORKED EXAMPLE

Example: build support before a diagonal threat

Starting position: You want a rising diagonal from the lower-left toward the upper-right.

Reasoning: Every upper piece needs occupied cells beneath it. Before dropping the third diagonal piece, check whether its target column has enough support and whether that support gives the computer an immediate four.

Takeaway: A diagonal plan is also a stacking plan; inspect the supporting cells before committing to the visible line.

Remember that pieces fall

You choose a column, not an arbitrary square. The piece occupies the lowest open cell, so every move also changes which square becomes playable above it. A harmless-looking drop can support an opponent’s winning diagonal on the next turn.

Check immediate threats first

Before attacking, scan horizontal, vertical, and both diagonal directions for a three-piece line with a playable fourth square. Take your own win immediately. If the opponent has one, block it. A square is only a real threat when gravity allows a piece to land there now.

Prefer central influence

Center columns participate in more potential four-piece lines than edge columns. Early central pieces can contribute to horizontal and diagonal plans on both sides. Still, central preference is secondary to a direct win, required block, or move that would make a dangerous square playable for the opponent.

Look one support move ahead

After choosing a column, ask what landing square you expose above your piece. If that new square completes an opponent line, your move is unsafe even if it creates a threat of its own. This one-ply support check prevents many avoidable losses on a compact board.

Editorial and correction notes

This page was checked against the game code and its visible controls. It does not present entertainment scores as medical, educational, or professional assessments. If a rule, score, or control behaves differently from this description, email songtianqi0920@gmail.com with the page URL, browser, and device.

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