Will Mr. Sinister be Science or Mutant?
After reading about Mr. Sinister's origin (I actively avoided X-Men comics throughout the 80s and 90s) I discovered that Mr. Sinister isn't really a mutant at all, but he did have his genome manipulated through various experiments, making him sort of a science-mutant (or a mutate as Marvel calls it, similar to Spider-Man). So which class should he be? Mutant or Science?