The antonyms for the word "makes legal" are quite broad and varied depending on the context of the word. However, some of the opposite terms could be "prohibits," "outlaws," "bans," "forbids," "condemns," "disallows," or "illegalizes." These words indicate the opposite sense of legalizing or making lawful. Moreover, they express the idea of prohibiting or preventing some actions or behaviors that could be harmful, dangerous, or unethical for the society or individuals. Thus, using the antonyms of "makes legal" could help convey a negative or restrictive connotation in a given statement or sentence.