Blitzball is played with a heavy medicine ball outdoors. The person with the ball is chased by others until the ball is passed. If the group catches up to the person with the ball before he passes it, then they can knock him down. When knocking someone down, you can't use your arms-- you have to cross them in front of you and butt the other person. If you get knocked down illegally, though, you can retain the ball and keep running. When passing the ball to avoid getting knocked down, if it hits the ground, that's a legal catch and the catcher can keep running. There are no teams because it's every man for himself. Hence, Gene can throw the ball to Bobby and then knock him down if he wants to do so. If a person refuses to catch the ball when thrown to him, he can do that, it is called the "Lepellier Refusal" (39).
The whole game reflects Finny's character because he is very athletic, competitive, strong, and able to beat everyone else without a team to help him. Gene best describes how Blitzball emphasizes Finny's character as follows:
"He [Finny] had unconsciously invented a game which brought his own athletic gifts to their highest pitch. The odds were tremendously against the ball carrier, so Phineas was driven to exceed himself practically everyday when he carried the ball. . . In such a onstop game he also had the natural advantage of a flow of energy which I never saw interrupted. I never saw him tired, never really winded, never overcharged. . ." (39).
Gene also explains that Finny was unbeatable when he had the ball. He would twist and turn and throw everyone off his trail to the point of the "wolf pack's" confusion. Gene saw Finny chuckling to himself whenever he surprised everyone with this athletic tricks. He even surprised himself, Gene says. Hence, Blitzball encompassed everything Phineas all in one game.