Bracketing: follow each uninterrupted capture line
A legal move needs more than contact with an enemy disc. Follow the ray until it reaches your own disc, an empty square or the edge, then decide whether anything is captured.
LEARNING CENTRE
Reversi: evaluate the replies behind the capture
Learn legal capture lines, the special status of corners, the choices a move leaves the opponent, and the exact conditions for a pass or finish. The playable comparisons show actual captures and legal replies, keeping these observations separate from claims about the eventual winner.
The rules in this version
Playfield's classic Reversi uses a six-by-six board with four starting centre discs. Violet moves first and alternates with Cream when both have legal moves. A placement must bracket one or more consecutive opposing discs between the new disc and an existing friendly disc in at least one of eight directions. Every bracketed line flips. The interface automatically passes a player with no legal move. The game ends when neither player can move, even with empty squares left; the greater disc count wins and equal counts draw. All discs count equally in this version.
Four decisions to understand
Corners: separate a permanent disc from a risky approach
A corner, once legally occupied, cannot be captured back. Moves near an empty corner deserve attention because they can create a capture line that makes it available to the opponent.
Mobility: count and inspect the opponent's choices
A large immediate capture can leave the opponent many good replies. Compare the legal moves available after a candidate placement, including the quality of those moves rather than only their number.
Passes and endings: legal moves decide when play continues
An empty square is not necessarily playable. Check both players' legal moves before deciding whether the turn changes normally, one player moves again or the game is over.
Two practice collections
Foundations: read the board before moving
Four studies in legal moves and their immediate effects. Make a prediction, test it, and compare the starting-position answer.
Decisions: compare what happens next
Four studies in future consequences. Distinguish a verified finish, a short tactical proof and a useful feature that does not establish a win.
What the evidence establishes
Capture legality, legal-move counts, corner stability, passes and final counts can be checked exactly. Mobility and avoiding access to an empty corner are strategic considerations, not universal winning rules. More legal moves, more current discs or ownership of a corner does not alone prove a final win. The regular game is local two-player play; example analysis is not an unannounced computer opponent or a claim of perfect strategy.
Each technique has two playable starting positions. The collection and print links reuse those same studies, so a lesson, a practice page and a printed sheet do not count as three different puzzles.
DECISION LAB
The corner loses. The quiet move wins.
Read a complete two-empty-square ending in which move order outweighs both the corner rule and the immediate disc count.
Test your prediction and follow the evidence →