In the training mode, there are mini-games where the player can train any career paths they want. However, in order to train to increase the player’s stats, no one can master all professions at the same time. Once the player trains to increase their stats, the stats of all 4 professions will be changed as well. There are complementary careers you can train, but be careful – some careers counteract each other. If the player takes a training course that doesn't match the current career path, their stats will not increase. Meanwhile, other career path stats will still be changed. See this table of stats obtained from training.