Historical clue formulations

• Professor Xavier's students, e.g. — 2024-11-09
• Blue lobsters and white tigers, e.g. — 2024-10-17
• The X-Men, for example — 2022-02-11
• Ones with X-Genes, in comics — 2017-06-29
• Staples of Marvel Comics — 2014-03-15
• Sci-fi creatures — 2005-12-05
• Certain spiders in "Spider-Man" — 2002-05-20