What are the rules of pool? Which game eight ball, nine ball, cutthroat, or something else? No matter. Like many games the rules are variable. The problem wasn't the moving of the ball, but the not asking if it was an understood rule or not. I'm by no means a pool expert. But I've played enough that I know there are variations. For instance I believe in league play scratching the que ball on a break is a loss, but most people don't play this way in a friendly game. Now what if any other balls were made on the break, usually this meant it was still an open table for the other team/player. But not always. What about using the eight ball (in eight ball) to knock another ball in, usually this is a forfeit of your turn even if you make the target ball or not, some people say it is cool. What about calling the shot? I've played games where you had to call every shot, others where you had to call every non-obvious shot, others where you absolutely had to call eight ball/nine ball shots, and still others where you didn't need to call anything. Usually House Rules are followed (in other words you play by the rules of whoever's house you are at), if you are at a neutral site the rules must be agreed upon.

Now in eight ball there isn't that much room for variation, but there is some. While I've never played where you can move the que ball off the rail, I don't see why this couldn't be allowed if it was agreed upon. I imagine this would only happen if all the players were pretty poor.

Some rule variations I've seen:

  • Slop: does sloppy shots count or not
  • foot on the ground: atleast one foot must be touching the ground, sometimes even flat, this comes into play when making rather difficult shots with the pool stick behind your back and sitting on the edge of the table.
  • calls: what shots do you have to call.
  • scratch on break: game over or not? In eight ball is it still open or not?
  • accidents: say you are not sober and you tap the que ball a quarter of an inch while preparing to shoot. Sometimes that is a shot, sometimes the ball is just reset.