Are also specified:
- The status of the alternate versions: "past", "future" or "alternate".
- The origin of the X-Gene (and of the mutation generally) for clones, artificial mutants, etc.
The list is divided in three categories:
- The human mutants Homo superior sapiens, and also Homo supreme:
- The Post-M-Day mutant..
- The Post-M-Day new mutants.
- The Non-Human Mutants, born from others forms of life, including aliens, robots and A.I.
The mutants who were powered before the M-Day, dead or alive, known or not, and who are currently living and confirmed.
Post-M-Day Mutants known before M-Day
The mutants who were already powered and alive at the time of the M-Day, and who haven't died and resurrected since, including:
- The living 198 (the human mutants known by the American Government).
- The time- or reality-travellers who made their first steps on Earth-616 before M-Day.
- The pre-M-Day clones.
Mutants discovered/revealed after M-Day
Mutants who were powered after the M-Day, but unknown before that event.
Mutants resurrected after M-Day
Include mutants dead but powered at the time of the M-Day, as well as characters alive after the M-Day, deceased and resurrected back, and also characters who were "recomposed", such as Nate Grey or Onslaught.
Mutants repowered after M-Day
Many mutants were repowered through various means after the M-Day.
Post-M-Day New Mutants
Mutants activated/born after M-Day
Mutants created after M-Day
This category include clones and humans having received mutant genetic material after the M-Day.
Time- or reality-travelers came after M-Day
Contrary to the preceding sections, not all individuals listed here are "classic mutants" with the X-Gene. As far as we know, the M-Day had no non-human victim. Are listed here the mutant confirmed as powered.
- For further explanation, please see the specific section in the article: Homo superior: Non-Human Mutants
- For a more complete list, please see the complete list of Non-Human Mutants