If there are multiple creatures in the art that each match what the card is representing, then that creature has four or more legs as long as any one of the matching creatures in the art has four or more legs. For example, Llanowar Elves (M19) has three figures in its art, all of whom are Llanowar elves. However, none of those figures has four or more legs, so Llanowar Elves is not a valid target for Jermane’s abilities. If even one of the figures had four or more legs, then the creature would be a valid target.