During a match, the aliance scores points by placing balls into goals, positioning the robot in the End Zone at the end of the match, moving the goals onto a semi-stable bridge which must be balanced at the end of the match, ending the match prior to the two minute time limit, or by carrying a robot across the field by using a stretcher if the stretcher is in the End Zone at the end of the match. Each alliance competes using four (4) team-built robots. There are forty (40) small balls, approximately 13 inches in diameter. There are four (4) balls approximately thirty (30) inches in diameter. Balls are inflated to size, not pressure. There are two (2) seven (7)-foot high goals with caster wheels around the bases that may be moved around the playing field. One goal starts near the Start Zone, the other starts near the End Zone. Dividing the field in half is an eighteen (18)-inch high railing with a central bridge. Robots may pass over the bridge or rails to access the opposite end of the field. The bridge is centrally supported on a beam approsimately six (6)-inches wide, such that it may tilt toward either end or remain level. At the start of each match, the alliance station contains twent (20) small balls. Twenty (20) small balls and four (4) large balls will be located at the far end of the playing field.