Cockroach Pig (曱甴路) is the third and final derived road, and the one players most often skip. It looks different from the other two — rows of diagonal slashes rather than circles — which makes it appear to be a separate system with its own rules.
It is not. Cockroach Pig runs the identical procedure to Big Eye Boy and the Small Road. The only thing that changes is how far back it looks: three columns. If you know either of the other two roads, this article will take you a couple of minutes.
Where it sits in the set
The three derived roads are one algorithm at three distances:
| Road | Looks back | Starts at | Symbol |
|---|---|---|---|
| Big Eye Boy | 1 column | Col 2 Row 2, or Col 3 Row 1 | Hollow circle |
| Small Road | 2 columns | Col 3 Row 2, or Col 4 Row 1 | Filled circle |
| Cockroach Pig — this page | 3 columns | Col 4 Row 2, or Col 5 Row 1 | Slash |
When Cockroach Pig starts
At Column 4, Row 2 of the Big Road, or Column 5, Row 1 if Column 4 never gets a second entry — whichever comes first. It is the last road to appear because it needs the most history before it has a column to compare against.
Both starting cases, on the smallest boards that produce them:
The two questions (again)
Question A — the Big Road started a new column
Compare the depth of the column that just finished against the depth of the column three further back. Same depth is red, different is blue.
Question B — the Big Road moved down a column
Look at the column three to the left, at the row you just landed on and the row above it. Both filled or both empty is red; one of each is blue.
A traced shoe
BBPPBBPPPBBBBBPPBPBBPPBPPB
Twenty-six hands. Every board below is drawn by the same road engine that powers our free Road Decoder:
The first six marks
The first mark appears as the Big Road goes down to Column 4, Row 2. Three columns back from Column 4 is Column 1, which is 2 deep.
- Red. Column 4, Row 2. Column 1 is 2 deep, so Rows 1 and 2 there are both filled. Same twice.
- Blue. Column 4, Row 3. Column 1 stops at Row 2, so Row 3 is empty and Row 2 is filled. The answer changed.
- Blue. New column — Question A. Column 4 finished 3 deep against Column 1’s 2. Different.
- Red. Column 5, Row 2. Reference is Column 2, which is 2 deep, so both cells are filled. Same twice.
- Blue. Column 5, Row 3. Column 2 stops at Row 2 — one filled, one empty.
- Red. Column 5, Row 4. Column 2 is now entirely above us, so Rows 3 and 4 there are both empty. Same twice.
Check against the diagram: red, blue, blue, red, blue, red. Mark 6 is the empty-empty case — two blank cells count as the same answer twice, so the mark is red. It is the single detail worth slowing down for on any derived road.
The ladder
Draw all three derived roads for this shoe and you get 23 entries, then 21, then 19. Each road is shorter than the one before it, by exactly the amount of extra history it needed before it could start.
Bead Plate
Big Road
Big Eye Boy
Small Road
Cockroach Pig
On a live table that descending length is the quickest way to confirm you are looking at the roads in the right order, before you read a single color.
Why “Cockroach Pig”?
The Chinese name is 曱甴路, usually translated as cockroach road; the “pig” in the English rendering comes from an older transliteration rather than from any second animal. The common explanation for the name is that the dense diagonal slashes look like insect legs scurrying across the screen.
The slash itself is only a drawing convention, chosen so the third road stays distinguishable from two rows of circles above it. It carries no meaning the other roads’ circles do not.
Does the third road tell you more?
It tells you the same kind of thing from further away — and it is worth being blunt about the limit of that.
Cockroach Pig is computed from Big Road columns that already exist. It introduces no new data; it re-expresses history you can already see. A board where all three derived roads run red means three lookback distances happened to give the same answer about hands that have already been dealt. That is a coincidence of arithmetic on the past, not a consensus about the future.
You now know all five boards
With Cockroach Pig you have the complete display: two boards that record results and three that measure how repetitive that record has been. If you want the whole set in one place, start from the complete guide to reading baccarat roads.
Then make it automatic. Enter hands one at a time in our Road Decoder — free, no account — and call each slash before it appears. Cockroach Pig is the easiest of the three to practise, because by the time it starts you have already read two roads’ worth of the same shoe.