Defense
The defense always has the right to make any adjustment before the down starts. The defense starts with twelve men. The offense starts with eleven men. The defense is given the extra checker because the quarterback is the most powerful player in the game. For the defense to score a safety, the ball carrier must be tackled in the endzone. After the defensive team scores a safety, the defensive unit then gets the ball for its offense.
Blocking
In accordance with the invention, defensive blocking is permitted to create obstacles for the offensive team. Only a single checker may enter into a block. Checkers can then be stacked creating a stack of checkers as high as can be allowed. Both the offense and the defense have an equal opportunity in controlling blocks. The checker on top controls the block.
Tackling
Only a single checker (one not involved in a block) may make a tackle on a ball carrier. A tackle is made when a single checker has the move from a square next to the ball carrier. When the tackler is placed on top of the ball carrier, the down is complete.
Intercepting
If the quarterback or ball carrier is passing the football and the pass hits the defender before it hits the receiver, then the pass is intercepted and it is the interceptor's move.