Kill Shot

The 3rd and final shot type is the kill shot.  It is the ultimate rally ender one way or another.  If you can pull it off, you win the rally.  If you skip it, your opponent wins the rally.  It's the riskiest shot in the game and requires excellent stroke mechanics to perform regularly.

The kill shot is hit 6 inches high or less on the front wall.  It is designed to be unretrievable by your opponent.  As you might imagine, it is very difficult to consistently hit a ball 6 inches high or less in racquetball.  That is the reason that the kill shot should only be used in certain situations.

Here is a more detailed description of the Kill Shot:

Contact the ball as low as you can within your hitting zone (see forehand stroke mechanics if you don't know what that means).  For a kill shot it is important to swing as level as you can.  As such, you should contact the ball as low as ankle high so that the ball travels parallel to the ground and directly toward the front wall.

The ball should leave your racquet and hit the front wall anywhere from 6 inches high or less.  The ball then travels away from the front wall, bounces once almost immediately, and takes it second bounce somewhere between "a few feet away from the front wall" and the foot-fault line.  Some kill shots even "roll out" away from the front wall, seemingly not bouncing at all (after you hit those it's time to wave to the crowd and take a bow).

Important: 

As mentioned, kill shots are rally-enders for either you or your opponent.  They are highly risky and should only be used if you are "set up" and the ball is within your hitting zone.  The more you go for kill shots, the more likely you are to skip the ball and give your opponent a free point.  If you have a chance to win the rally with a pass or a kill, always take the pass.  You're less likely to skip it.

Check out this video of the killshot.

Now that we understand the 3 different ball heights that are used for offensive shots in racquetball, let's move on to the actual shot-types.