Skills, Perception, and Proficiency

In some situations, you need to know the creature's proficiency rank in a skill or other statistic. Creatures are trained in the skills listed in their stat blocks and untrained in skills that aren't listed. A creature usually has expert proficiency in its listed skills around 5th level, master proficiency around 9th level, and legendary proficiency around 17th level. A creature might need a certain proficiency rank in Perception to detect certain things. Many creatures have expert proficiency in Perception and improve to master proficiency around 7th level and legendary proficiency around 13th level. At your discretion, creatures with galaxy-renowned aptitude for a particular skill or in Perception might have a higher proficiency rank in that skill or Perception.