Borg had tremendous topspin and steadiness. Rosewall had a fantastic backhand. Connors an amazing return of serve. McEnroe a devastating serve and volley. The list of champions and their weapons is exhaustive.
Weapons have their roots in a player's mental, physical and emotional makeup.
Steffi Graf's speed and athleticism translate into a potent serve and forehand, capable of hitting many winners and forcing shots. Borg's speed, superior endurance, and temperament precipitated an almost impenetrable steadiness that would grind opponents into the ground. Connors had outstanding footwork and racket preparation as distinctive competencies. He was able to parlay these into the ability to hit penetrating groundstrokes much earlier than the opponent, keeping him on the defensive most of the time, a competitive advantage. So , figure out what you do well naturally, and build around it.