What is Career Mode
Career mode is racing through the ranks against game created opponents. Each opponent has a unique style of racing and varying degrees of difficulty. The idea behind career mode is that you take the slowest car and race your way to the fastest car, earning points along the way. There are three types of racing with each car and level. They are King of the Track, grudge racing, and Official Events, and are discussed below.
King of the Track
King of the Track is an event where you race each character trying to beat all 20 in one shot. If you win a race, you advance to the next character. If, at any point, you lose, you have to start all over again. Each opponent pays more than the opponent before them. King of the Track is also the only type of race you can race as many times as you'd like, so it is a great way to practice and to earn points.
Grudge racing is a standard race with a small twist. At the end of the race, you don't see the time your opponent ran. The idea is that you never know what your opponents run so there is always the chance that they will be faster than you. Grudge racing pays based on difficulty and you can only race each opponent once. If you lose to any opponent, you are unable to challenge them again, and won't be able to win points from them.
Official events is a single elimination tournament that is for the best of the best at each level. You have two chances to qualify in the top 16, or else you don't even get a chance to race in the tournament. Once the tournament begins it matches you, based on qualifying position, against an opponent. The winner moves on to the next opponent until there is one final winner. If you lose, you have to start all over again which includes having to qualify.
King of the Track and grudge races are optional, but the official event tournament is required in order to advance to the next level and the next car. Once you beat the tournament for a given level you are automatically moved to the next level. When your beat the tournament for level 3, you have completed that car and can buy the next car from the dealership if you have enough points. If you don't have enough points you can continue to race King of the Track until you have the points, or you can click the green plus "+" sign in the top right of your screen and buy coins.
Unlocking New Cars and Levels
Each car has three levels to career mode, level 1, level 2, and level 3 with each level increasing in difficult. In order to unlock the next level you must beat the level you are currently on. In order to unlock the next car you must beat level 3 in your current car. You beat a level by winning the "Official Events" tournament for that level. When you beat level 3 you unlock the very next car in the dealership.
If you want to unlock a car immediately without beating level 3 in a car, or if you want to race the cars in a different order than you'd unlock them in career mode, you can click the green plus "+" sign on the top right of your screen and purchase coins. If you buy a car with coins that car is immediately unlocked, even if you haven't unlocked the cars before it.