Cat and No-Cat
After the perpendicular opening (f5 d6), Black's c4 on move 3 leads to the Cat or the No-Cat. The Cat goes f5 d6 c4 d3 c5; in the No-Cat White plays g5 on move 4, and c6 on move 5 makes it the Swallow.
For each move: discs flipped, openness, and the opponent's legal moves right after it. These are counts, not an evaluation of who is better.
Cat
Moves: f5 d6 c4 d3 c5
Continues from the Perpendicular opening with c4 d3 c5.
Drill this line as Black · as White
| # | Side | Move | Flipped | Openness | Opponent's moves |
|---|---|---|---|---|---|
| 1 | ● Black | f5 | 1 | 4 | 3 |
| 2 | ○ White | d6 | 1 | 4 | 5 |
| 3 | ● Black | c4 | 1 | 4 | 5 |
| 4 | ○ White | d3 | 1 | 3 | 7 |
| 5 | ● Black | c5 | 1 | 2 | 6 |
No-Cat
Moves: f5 d6 c4 g5
Continues from the Perpendicular opening with c4 g5.
Drill this line as Black · as White
| # | Side | Move | Flipped | Openness | Opponent's moves |
|---|---|---|---|---|---|
| 1 | ● Black | f5 | 1 | 4 | 3 |
| 2 | ○ White | d6 | 1 | 4 | 5 |
| 3 | ● Black | c4 | 1 | 4 | 5 |
| 4 | ○ White | g5 | 2 | 5 | 5 |
Swallow
Moves: f5 d6 c4 g5 c6
Continues from the No-Cat with c6.
Drill this line as Black · as White
| # | Side | Move | Flipped | Openness | Opponent's moves |
|---|---|---|---|---|---|
| 1 | ● Black | f5 | 1 | 4 | 3 |
| 2 | ○ White | d6 | 1 | 4 | 5 |
| 3 | ● Black | c4 | 1 | 4 | 5 |
| 4 | ○ White | g5 | 2 | 5 | 5 |
| 5 | ● Black | c6 | 1 | 2 | 5 |