The mounts are horses, mostly thoroughbreds, no ponies are allowed in Polo. The object of the game is to score as many goals as possible. There are four players on a team and each assumes a specific position (wikipedia) either offensive or defensive. However, given the enormous size of the playing fields, the momentum of the galloping horses and the balls unexpected changes of direction, the game is very fluid, and the positions continuously change. There are few set plays in polo.
Having a good is almost like a sixth sense in the game. With thousand pound animals running at speed there is a pre-eminent necessity for a right of way rule. The central concept in the rules of polo is the line of the ball, a right-of-way established by the path of the traveling ball. Like the rules of the road, there are dos and donts governing access to this right-of-way and crossing it. Within these limitations, a player can hook an opponents mallet, push him off the line, bump him with his horse or steal the ball from him.
Penalties are awarded as free hits. The more severe, the shorter the distance to the goal. The closer hits are almost certain goals. After every goal is scored, the teams change sides in order to compensate for field and wind conditions. A typical score would be 10-7. Polo games are played on the flat or the handicap. Every registered player is awarded a skill rating from C (- 2, the lowest) to 10 (the highest). When a match is played on the hand. The Players are matched up based on their skills so that the game can be pretty fair.