Louie The constructor struts pieces to their location. The Girders are constantly moving back and forth. It is your job to lock them down, and then get back to where you started the level. There are 100 levels, and two types of levels. One is just locking down, the others you have to put them in a specific location. There are three levels of difficulty to choose from, you just get paid more the harder the level, and you have less time to complete the level.