The 2nd highest rank among WORLD. Their missions are often times more difficult than a Junior Officer's. Normally, once a Junior Officer has surpassed the expectations of the Commander, only then will the Junior Officer be promoted to Senior Officer. Senior Officers are often times the ones who do the more serious work for the Commander. The only difference between Senior Officers and Junior Officers is that the Senior has more experience. Rarely, they will accompany Junior Officers on their mission. They may also be assigned a Trainee to teach and train to become a Soldier or Junior Officer. Senior Officers, are, more or less, the main body of WORLD.