 TM points must be used to learn the skill initially, and the person's TM level must also be high enough to learn the skill.Once a skill reaches a certain level by putting TM points into it, the skill can be mastered for it to be any further improved, This is also the final improvement and provides a more powerful boost to the skill than any other improvement.To master a skill, the player must go to a skill master who will then tell how much of an item the player needs to get, along with how many TM points needed to master the skill.