The people in the back of the pack during a multiplayer Mario Kart race. The 3rd place player is usually considered the "conductor", and everyone behind him is part of the train. The reason for the label "mediocrity" is that farther back player always get much better items that allow them to "cheaply" make up ground. A common scenario is that 1st and 2nd will be skillfully sparring for first place,and blue shell comes from the back of the pack and destroys the leaders. While they are the down the "conducter" and his "train" will pass the more skilled players while making whistling sounds.

When some little bitchboy is acting like a little tiny pee pee poo poo baby and messing up the group plans.