your character's class will gain 50% more experience from everything as long as it is below the level of your highest level class of that category. combat classes, such as disciples of war and magic, count as one category together for this purpose, not sure about land and the hand. but i think the 2 might be seperate categories. this means you get 50% more experience from a lot of stuff if you have a level 50 and are leveling something that isn't level 50