4

Parry three defends a very small piece of target area. A commonly used sabre parry, the three or tierce, is rarely seen in foil or epee so can be used to your advantage once you have mastered it. It defends a very specific threat (a cut, or flick)to a very specific line (the back or back of the of the arm.)
When done properly it can put you in position for to deliver a quick and powerful riposte.

Parry five is the most commonly misused parry. When fencers swing too hard at the four, they think they have invented the five. Like other pronated parries, it defends well against cutting or flicking actions, but is weak on the riposte unless the fencer using it has excellent distance and not a little power. This is well used against lefties trying to flick right-handers chests and vice-versa.

The two or seconde parry is powerful and can knock a fencer attacking in the low line off balance if you take enough blade. The riposte has a long distance to travel but if used sparingly, your opponent will not have recovered in time. Another advantage of the two is that it has so many options of which line to riposte to, there can be no conditioned response to it. Fencers must roll the dice and parry where they think you will riposte or they will be too late.

The first parry (usually called the Prime) Is a very useful tool. It has weaknesses: if used too often it can become an easy target. since it opens up a large piece of lame. It must be used in conjunction with a step forward and to the right.
It is almost more of a counter-attack than a parry, since you step into the attackers distance at the same time as you take the blade. For this reason it is risky, but once you are comfortable with it, you will find it a great way to take advantage of over-exuberant attackers.

Footnote: The five or Quinte parry illustrated here is used in foil. In sabre the head parry is often called the quinte as well. an illustration will follow. Or not.

"Where'd they get these crazy numbers?"
The parries were first numbered by the Italian fencing master Agrippa.
They start with the blade in it's scabbard on the hip opposite the sword arm (as was the style at the time) and proceed to the nearest open line.
I.E. One (or "prime")defends the inner line but leaves the outer line open. Two defends the outer ine but exposes the back of the sword arm which leads to three, and so on and so on and so on....