These support cards are companions that some characters get at the start of a scenario. (The Core Set does not include any characters that use cohorts; they can be found in certain class decks and Adventure Paths.) If the back of your character lists a cohort at the bottom of your deck list, after you draw your starting hand, add your cohort to it. If you encounter a cohort in a location, you automatically acquire it. If you would banish a cohort from a location, you may encounter it instead. Otherwise, if you would banish a cohort, remove it from the game instead; it may not be used in future scenarios, even if it’s listed on your character.