TECHNIQUE 2 OF 4
Immediate wins: test the legal drop, then all directions
Before improving a position, check whether a move already ends the game. Inspect horizontal, vertical and both diagonal directions through the newly placed token.
The rule and its limit
Simulate a legal drop for the player to move. It is an immediate win if the resulting board contains at least four consecutive tokens of that player on a straight permitted line. Tokens separated by an opposing token or an empty gap are not consecutive. Multiple winning columns can be equally valid immediate choices.
A common mistake
A total of four tokens somewhere in a row is not enough. Also, checking only the horizontal line can miss a vertical or diagonal finish.
PLAYABLE EXAMPLE 1
Take the win on this turn
Violet to move. Find a move that wins immediately before considering a defensive move.
Loading playable study…
Use the column buttons to drop a token. Orange (O) and Violet (V) take turns. You control both sides here; there is no computer opponent. Test a reply, then undo to compare another.
Keyboard: Tab to an enabled control, then press Enter or Space. The study starts from the diagram shown; reload can restore your own saved moves.
Try the task before inspecting the answer.
Compare the starting moves
Immediate winning columns: 2, 3. A win ends the round before the opponent can answer.
| First move | Immediate effect | Checked consequence |
|---|---|---|
| Column 1 | Lands at R2C1. | Forces a win on your next turn against every legal reply. |
| Column 2 | Lands at R3C2. | Wins immediately. |
| Column 3 | Lands at R3C3. | Wins immediately. |
| Column 4 | Lands at R3C4. | Forces a win on your next turn against every legal reply. |
| Column 5 | Lands at R5C5. | Forces a win on your next turn against every legal reply. |
| Column 6 | Lands at R6C6. | Forces a win on your next turn against every legal reply. |
| Column 7 | Lands at R5C7. | Forces a win on your next turn against every legal reply. |
PLAYABLE EXAMPLE 2
Check every winning column
Violet to move. Find a move that wins immediately before considering a defensive move.
Loading playable study…
Use the column buttons to drop a token. Orange (O) and Violet (V) take turns. You control both sides here; there is no computer opponent. Test a reply, then undo to compare another.
Keyboard: Tab to an enabled control, then press Enter or Space. The study starts from the diagram shown; reload can restore your own saved moves.
Try the task before inspecting the answer.
Compare the starting moves
Immediate winning columns: 2, 3. A win ends the round before the opponent can answer.
| First move | Immediate effect | Checked consequence |
|---|---|---|
| Column 1 | Lands at R1C1. | Forces a win on your next turn against every legal reply. |
| Column 2 | Lands at R3C2. | Wins immediately. |
| Column 3 | Lands at R3C3. | Wins immediately. |
| Column 4 | Lands at R3C4. | Opponent can win next in column 1. |
| Column 5 | Lands at R4C5. | Opponent can win next in column 1. |
| Column 6 | Lands at R6C6. | Opponent can win next in column 1. |
| Column 7 | Lands at R5C7. | Opponent can win next in column 1. |
Four tokens with a gap are not four in a row
Orange tokens occupy bottom-row columns 1, 2 and 4. Bottom-row columns 3 and 5 are empty. Consider a drop by Orange into column 5 and only the horizontal line described.
The tempting move
Count the four Orange tokens at columns 1, 2, 4 and 5 as a horizontal win.
Why it fails
The empty square at column 3 splits them into two pairs. They are not consecutive.
What you can conclude
That horizontal line is not a win. A drop at column 3 would join columns 1–4 instead. Other directions must still be checked before making a whole-board claim about the column-5 move.
Try the idea in another position
Orange has tokens at R6C5, R5C5 and R4C5. R3C5 and the higher squares of column 5 are empty, and it is Orange's turn. What does a drop in column 5 establish?
Check your reasoning
The token lands at R3C5 and creates four consecutive Orange tokens in column 5. That is an immediate win, regardless of longer-term plans elsewhere on a previously unfinished board.