About the Skill:
The Peacemaking skill is one of the Bard-themed skills and is sometimes called Peacing for short. In a nutshell, the soothing music of a successful attempt causes those to whom it is directed to relax and stop fighting. To successfully be able to use this skill also requires some level of Musicianship skill as well. While a useful skill for a Bard in it's own right, it is also valuable to possess, or assist other players with, when it comes to Animal Taming or Treasure Hunting.
Peacemaking skill has two different modes, Area Peacemaking and Targeted Peacemaking.
Activate the skill via macro or skill button and target yourself. If successful, all aggression in the area will cease for a few moments. Players will have to re-attack their targets.
Activate the skill via macro or skill button and target a creature. If successful, the targeted creature will either remain non-aggressive or stop attacking it's target until a sufficient attack upon it breaks the trance or the bard loses line of sight for more than 10 seconds.
Each time Targeted Peacemaking is attempted, a difficulty check is performed based on the creature's Barding Difficulty versus the attempting character's combined skill in Musicianship and Peacemaking.
How to train:
Obtain a few dozen musical instruments, either from a carpenter or NPC. Use the Peacemaking skill and target yourself(Area Peacemaking). Repeat until the desired level is achieved.
Bear in mind that being able to attempt Peacemaking on some higher-level creatures, such as Balrons or Ancient Wyrms, requires extremely high levels of Peacemaking due to their high Barding Difficulty rating.