I am writing this based mostly on my own research. This section of the guide discusses the rival system.

Rivals

There are 133 rivals in the game (not counting the Devas and Devils), divided into 20 teams.

Below is the list of teams with how many rivals are in the team (including the leader), and typical winnings from one of the team members, excluding the leader (leaders usually give between 50% and 150% more than what is shown): [Team: # of Rivals, Typical Winnings] Rolling Guy: 4, 700 CP Curving Edge: 5, 700 CP SS Limited: 6, 1000 CP Elegant Wild: 6, 1200 CP Max Racing: 8, 1700 CP Diamond Image: 6, 1800 CP Fine Drive: 8, 2100 CP Twister: 6, 2500 CP R-Gangs: 7, 4700 CP Tokio Jungle: 7, 3400 CP Top Level: 6, 3500 CP Free Way: 9, 5500 CP Another Star: 5, 5500 CP Speed Box: 6, 6500 CP TR Racing: 6, 6500 CP Cupid Arrows: 6, 9000 CP Wind Stars: 9, 9000 CP RR: 8, 13000 CP Rings: 6, 16000 CP Speed Master: 9, 19000 CP (Notice the high value of R-Gangs and Cupid Arrows compared to their difficulty. I have even sometimes beaten RR rivals with the starting car.)

Below is the list of Devas and Devils with how many team leaders are required to beat before they will challenge you, and typical winnings: [Rival: Leaders Needed, Typical Winnings] Grim Reaper: 2, 16000 CP Midnight Cinderella: 4, 16000 CP Nocturnal Wolf: 6, 21000 CP Banshee: 8, 26000 CP Red Devil: 11, 26000 CP Exhaust Eve: 14, 52000 CP ZERO: 17, 52000 CP ???: 20, 52000 CP

Challenging Rivals

It is important to waste as little time as possible not racing rivals. Minimizing this time is never straightforward, but you should keep a few things in mind:

• If you are inbetween two new racers it is almost always faster to wait for the one behind you.

Not much is known about what determines which 6 racers will spawn on track each night, but I am led to believe the following:

• The performance of your car does NOT appear to affect which rivals spawn. (I did a bunch of testing and statistics and got only a 2% correlation and p<0.89, which is statistically a null result.)
• Sometimes one or more mid- or late-game rivals will spawn very early on, which, if they can be beaten, can provide a large cash influx early on.
• In my own experience, I have never gotten White Witch (Speed Master) to spawn on the B track, but I think she is the only one. It is possible there is a rival who never spawns on the A track, but I play B track too often to know. Aside from this, I do not think choice of track affects spawning.
• It is possible that beating some members of a team might make it more likely for more members of that team to spawn, but I suspect this is a statistical illusion.

Receiving Challenges

The team leader will challenge you after beating all rivals in their team. The next Deva or Devil will challenge you after beating a certain number of team leaders. If you quit to Main Menu before a race is over, it will NOT count as a loss! This can be exploited in two ways: First, since you earn 20% less for beating any rival after the first attempt, you can quit when you're about to lose and try again later without losing any potential winnings. Second, and more importantly, you can control when the team leader or deva/devil challenges you, which can be helpful in certain situations. After beating any rival, you will be challenged by the following (in descending order of priority):

1. If you just beat the last member of a team, you will be challenged by that team leader.
2. A deva/devil if one is ready to challenge. (This cannot happen more than once in a night, and previously losing to said deva/devil can delay this a little or cause the deva/devil to spawn as a normal rival on track.)
3. A leader of a team for which you have already beaten all the rivals. (This cannot happen more than once in a night, and previously losing to said team leader can delay this a little or cause the team leader to spawn as a normal rival on track.) If you are in the first half of a race with a team leader and drive by a normal rival whom you also need to race, it is often faster to retire from the race, race the normal rival, and then let the team leader challenge you at a later, more convenient time. You will lose a little money doing this, but time is much more important than money.