Teacher should discuss Enemy's act() method. Teacher explains how to use local variables in the code, for example to use “rotation” variable. Teacher should describe difference between this.rotation and rotation. Teacher should describe getOneIntersectingObject(_cls_) method behavior. It is used and instance is stored in proper local variable (class casting is required). If there is no intersection object it returns null value. Based on the performed boolean evaluation, an appropriate acting is performed (i.e., rotating or turning). The results are discussed by the teacher and peers.