In games, you will take part in any other group , through these you can add more experience, and you can add more energy and blood, when you turned more ,you can killing monsters. only killing, you can get more equips ,energy and so on. when you have WoW Power Leveling, you can have more and more! That is change yourself. 
Once you have World of Warcraft Power Leveling, you can add mood, experience, when you fight again, you will see more different monsters, just like strange monsters. Players often make own useful things for my own, so you can recognized the meaning of the game. That is why so many people still like it!