1. The most iconic core group of X-Men from the late '70s into the mid '80s have never been a team on screen, and as a result key relationships have never been written into a film.
2. You never get to see Wolverine and Nightcrawler be best friends.
3. You never see a "fastball special," i.e., Colossus throwing Wolverine at a bad guy.
4. You never see the tortured romance of Colossus and Kitty Pryde.
5. You also never meet the teleporting mutant sorceress Illyana Rasputin, who is the younger sister of Colossus.
6. You never see Kitty Pryde's pet dragon Lockheed.
7. You never see anything resembling the '90s lineup either, which everyone knows from the classic animated series and the Jim Lee era of comics.
8. You never see the tortured romance of Rogue and Gambit.
9. You never see the tortured romance of Archangel and Psylocke.
10. You also never see Rogue's tortured romance with Magneto.
11. The X-Men never go to space, and never encounter the Shi'Ar Empire.
12. They also never encounter the creepy, bodysnatching alien race known as the Brood.
13. You never see the Morlocks, the society of mutant outcasts who live in the sewers below Manhattan rather than in a mansion like the X-Men.
14. And you never see Storm become leader of the Morlocks after defeating Callisto in hand-to-hand combat.
15. You never see Storm's infatuation with the Japanese thief Yukio, or how that inspires her to ditch the goddess look in favor of a street punk aesthetic.
16. You never see Storm lose her powers, or her tortured romance with Forge, the man who created the machine that robbed her of her connection to the elements.
17. You never see Mystique's not-so-tortured romance with Destiny.
18. You never see Genosha, the island nation whose economy thrives as a result of the government brainwashing and enslaving mutants.
19. You never see the rivalry of Bishop and Gambit.
20. You never see Jason "Mastermind" Wyngarde, the creepy illusion-casting mutant who torments Jean Grey.
21. You never see Mister Sinister, the Machiavellian and ultra-glam geneticist obsessed with Cyclops and Jean Grey's genes.
22. You never see Cassandra Nova, Charles Xavier's genocidal non-corporeal twin sister.
23. You never see the malicious telepath Amahl Farouk, a.k.a. the Shadow King.
24. You never see the tortured romance of Cyclops and Emma Frost after Jean Grey dies.
25. You never see the X-Men play baseball.
26. You never see Iceman come out as gay.
27. You never see Wolverine as Kitty Pryde's mentor.
28. Or as Jubilee's mentor.
29. Or as Armor's mentor. Wolverine just loves to mentor teen girls, OK? It's not weird.
