The term "more fireball" typically refers to an extreme level of intensity or excitement, often associated with bold or daring actions. Some antonyms for this expression might include "calm," "mild," or "moderate." In a more literal sense, "less fireball" might suggest a reduced level of heat or energy. Other possible antonyms for "more fireball" might include terms like "lowkey," "subdued," or "laid-back." Depending on the context, these words might suggest a certain level of relaxation or restraint. Ultimately, the antonyms for "more fireball" will depend on the specific meaning and significance of the term within a given conversation or situation.