Healers in MMORPGs are typically characters dedicated to healing. They can often do damage as well, but their main goal is usually to heal other players on their team. Atlantica Online is a bit unique, since each player controls a whole team, a main character and up to 8 mercenaries. Thus, Atlantica doesn't have the concept of main classes that are pure dedicated healers, but rather has several main classes that have healing skills can heal significantly enough that they may not need a dedicated healer mercenary.