In Legend of the Streets, there are some ground rules to help facilitate this battle style. And here we'll clarify some of the descriptions from the wikipedia statement for LotS.
All Cat and Mouse runs in LotS must start using the "Rolling Start" method. the rolling start method is position where the lead car will be in front and the chaser will be at the back. If both cars have similar PP, the rolling start can start from the long straight.
Usually the recommended place to start is the entry into the first corner. That means rolling start and then go flat out into the first corner.
All races have to be done in Race mode with only 2 players. This is so that checkpoints will be able to calculate the time gap distance between players.
On First Lap:
Before the race started, the two rivals discussed already and the R34 will be the leader on the first lap. Race starts from the long straight and ends at the full lap check point.
Leader: Subaru IMPREZA WRX STI '07
Chaser: Nissan Skyline GT-R V·spec II Nür (R34) '02
Leader Win Condition: Lead and increase the gap above 1 second .
(2.0s for Silver and 3.0s for Bronze)
Chaser Win Condition: Overtake and maintains his lead until the finish line.
At the end of the finish line the R34 could not widen the gap above
1 second (2.0s for Silver and 3.0s for Bronze) and the WRX could keep up, so there is no winner/loser yet. The Gap was 0.420 seconds, so as a result a second battle will take place.
On Second Lap:
The two rivals swap positions and the battle goes into round 2.
Leader: Nissan Skyline GT-R V·spec II Nür (R34) '02
Chaser: Subaru IMPREZA WRX STI '07
Leader Win Condition: Lead and increase the gap above 1 second .
(2.0s for Silver and 3.0s for Bronze)
Chaser Win Condition: Overtake and maintains his lead until the finish line.
Here again, the WRX was able to maintain it's lead and the R34 was able to keep up within the
1 second (2.0s for Silver and 3.0s for Bronze) gap. So there is no winner/loser yet. Although the WRX sustained some damage on the rear left, he still maintained the lead. The Gap between the two cars was 0.429 seconds. The result will be a final battle on lap 3.
Third Lap:
Since this is a Cat & Mouse - 3 Laps, a winner will be decided in this round.
The leader and chaser position will be discussed and mutually agreed between the two rivals, in this case, the R34 is the leader once again.
Leader: Nissan Skyline GT-R V·spec II Nür (R34) '02
Chaser: Subaru IMPREZA WRX STI '07
Leader Win Condition: Lead and increase the gap above 0.5 second.
(1.0s for Silver and 1.5s for Bronze)
Chaser Win Condition: Chase and decrease the gap below 0.5 second (1.0s for Silver and 1.5s for Bronze) or overtake and maintains his lead until the finish line.
Notice the damage on the WRX, it is still there. They didn't go into the pits because it is not allowed and the battle will continue.
At the end of the race, the WRX wins. He won by overtaking the R34 and maintaining his lead until the finish line. Thus taking the win. The WRX didn't automatically win right after overtaking the R34.
What If Scenarios:
If the R34 had maintain his lead with a gap of more than
0.5 second (1.0s for Silver and 1.5s for Bronze), he would have been the winner. If the gap is less than
0.5 second (1.0s for Silver and 1.5s for Bronze), the WRX wins.
If the 3rd lap scenario was played in Lap 1, the WRX would have won the battle in Lap 1 and there will not be any lap 2 or lap 3.
If the 3rd lap scenario was played in Lap 1, and the R34 managed to retake his position by the end of the finish line, the battle will go into Lap 2.
Legend of the Street's Cat & Mouse - 3 Laps (CM3) is not a best of three. Whoever meets the win condition first wins. A three lap format is used so that a winner will be decided at most 3 laps. That's when Lap 3's gap becomes the deciding factor of who will win.
If you want purely Initial D style cat and mouse, choose LotS Cat & Mouse - Sudden Death (CMSD). This one, the battle will only be decided if the gap is increased or someone overtakes.