Befriending Pikmin are so shiny you can't miss them, so they're easy to find in caves. Once an enemy is at a particular amount of health the Befriending Pikmin will tame it. For example, once a Bulborb's health is 1/2 down, it can be tamed or if a Lavawraith's health is 5/6 down, it can be tamed. Looking at Befriending Pikmin will have you see your reflection.