The campaign is average but the online great
there is 4 different classes
Scout-can turn invisible a walk right up behind someone (great for campers),transforms into a car
Scientist-can heal others with a special grenade and ray gun and deploy a turret,transforms into a jet
Leader-can strength others with support abilities,transforms into a truck
Soldier-has the best weapons and most health,transforms into a tank
The abilities that I just mention are avaliable from the begining of the game no leveling up required, but when you do level up you get new abilities and ways to make old abilities better
Without the special abilities and transforming this game would be boring and thats what makes the game
my only complaints are the repetitive campaign and occasionally being diconnected but overall this is a great game