Introduced in the Hot Summer Update, Car Mastery (or just Mastery) is another single player game mode. It offers 15 single-lap races, called Challenges, for each car of the game, with the possibility to earn Credits, Car Upgrades, Pro Boxes, Boosters, and Licences. The announcing pop-up hints that this mode is only available for players with at least 135 stars in the Career Mode.
For each car in the game, there are 15 Races available, in increasing difficulty: the cars of your NPC opponents will be gradually increase from initial rank to max to max+pro. To be able to accept a challenge, i.e. take part in the race, you have to complete the previous challenges. Also your car has to have a certain level, challenges 1 to 5 being available without upgrades, increasing until Challenge 15 which requires a maxed and pro'ed car. While Challenges 1 to 10 have traffic, Challenges 11 to 15 are without traffic (except for the usual stationary vehicles).
Challenges are either of type Classic, Unplugged or Flawless. Classic means you have to finish first, Unplugged means finish first without Nitro refills on the track, and Flawless finish first without crashing: if you crash, you are immediately disqualified, and the race ends, without credits earned.
Licences work as an experience level, similar to the star system, which you cannot buy but only earn. However instead of giving you access to new levels, the licences give you access to new Decal packs, as well as some cars apparently exclusively available through licences: Camaro Z/28 (300), Datsun 280Z(650) and Shelby Cobra 427(1050). See the detailed contents of each decal pack on the page Car Mastery Rewards.
The Mastery mode is interesting for farming in the classical sense once you have pro'ed your Class S or Class A car:
The 15th challenge for the Lamborghini Veneno in Alps pays 5,845 for less than a minute of driving (versus the Season 9 race which takes at least 1'30 and pays 4,725) or the McLaren P1 15th challenge in Temple Drive which pays 5,915.
But not all pro'ed cars are suitable for farming, for instance for the Mercedes-Benz Silver Lightning in Tokyo gives 5,925, but because Tokyo is a long track and the race type is Unplugged, the credits per second are not very high. Also the opponents are at the same car upgrade level, you risk to not finish first if you crash.
However in a less strict sense of the term, you can earn a lot of credits while playing, independent of you car level: among all races of all cars, the total of Race Rewards are estimated to 4,500,000, the medals reward around 400,000, and the Challenge Rewards 11,000,000, not counting the value of the Pro Boxes, Boosters or car upgrades.
For each race you play in the Mastery mode, you get a number of rewards. Similar to events, you can cash in those rewards after the race, or you can decide to leave them for later.
For each Challenge you get a Credits reward, and for Challenge 5, 6 (mostly), 10 and 15 you get an additional reward amongst the following:
- Tuning Kit
- Nitro Starter
- Free Upgrades
- Upgrade for Class D
- Upgrade for Class C
- Audi R8 e-tron #10
- Cadillac ATS #10
- Mini Cooper S Roadster #10
- Ferrari 308 GTS 2*#5
- Geely GC9 2*#5
- BMW M3 Sedan 2*#10
- Audi RS 3 Sportback #10
- Mercedes-Benz SLS AMG Electric Drive #10
- Audi TTS Coupe #10
- Chevrolet Camaro GS #10
- Infiniti FX50 #5
- Audi RS 4 Avant #5
- BMW M1 2*#10
- Alfa Romeo 8C Competizione #5
- SRT 2013 Dodge Challenger SRT8 2*#5
- Upgrade for Class B
- Renault CLIO R.S. 200 EDC #10
- Lamborghini Urus #10
- Lotus Exige S Coupe #10
- Volkswagen Golf Design Vision GTI #5
- DS Survolt #10
- Aston Martin DB9 Coupé #10
- Lamborghini Countach 25th Anniversary #10
- Lotus Evora Enduro GT #5
- Ferrari Testarossa 3*#5
- Aston Martin V12 Zagato 2*#10
- Ferrari 458 Italia #10
- Mercedes-Benz Biome 2*#5
- Lamborghini Gallardo LP 560-4 2013 2*#5
- Spada Codatronca TSS 2*#10
- Ford Shelby #5 2*#10
- Upgrade for Class A
- Nissan GT-R (R35) #10
- Lamborghini Gallardo LP 560-4 2013 2*#10
- Cadillac CTS-V Coupe Race Car #10
- Mercedes-Benz SL 65 AMG Black Series #10
- Dodge Viper SRT10 ACR-X #10
- Marussia B2 #10
- Chevrolet Corvette C7 2*#10
- RUF RT 12 S 3*#10
- Ferrari LaFerrari #10
- Savage Rivale GTR 2*#10
- McLaren P1 #5
- Ferrari 330 P4 3*#10
- Upgrade for Class S
- Extra Tank
- Double Credits
- Pro Box