So, this is one of those things that probably only me has even noticed, let alone would care about, but here goes. In the recent Civil War II #3, (recapped over at Comic Book Resources) a fair-sized batch of earth's heroes confront Bruce Banner, based on the prediction from the Inhuman Ulysses that the Hulk would murder the Avengers. This would be moments before Hawkeye would murder Banner, but hey, look! It's Nightcrawler, between Captain Marvel and Banner.
Except he wouldn't have been there. We looked at Civil War II: X-Men #1 back in June, and Kurt had already switched to Magneto's side. He wouldn't have gone there with Storm, since he had already been established as against punishing anyone for crimes they hadn't committed yet.
This kind of continuity error isn't unusual by itself--there's over 25 characters in that CWII panel, and there could even be other mistakes in it--but it is notable, in that something similar has happened to Nightcrawler before, in another big crossover sequel, Secret Wars II #9! You can see Kurt on the cover, where he and Hawkeye appear to have landed on the bottom of the superhero dogpile; and he appears a couple times in the issue as well.
You have to be looking for him, and Nightcrawler doesn't have any lines in this one; but with the dialog in this series he's not missing much. Look, there he is again.
Except Nightcrawler wasn't there, either! His religious beliefs were difficult to reconcile with the omnipotent Beyonder, and he had freaked out a bit. Kurt doesn't appear in the next two issues of X-Men, where Rachel Summers would try to kill the Beyonder; #204 would be "What Happened to Nightcrawler?" as Kurt tried to get his groove back.
I think Nightcrawler even makes another appearance in CWII, teleporting a prisoner away, even though that doesn't fit with how his powers usually work: he shouldn't be able to port somewhere he can't see and hasn't been, for fear of appearing inside something. In the same vein, Kurt's usual range is maybe a couple miles in a single teleport, yet in the most recent issue of Extraordinary X-Men, Kurt appears to teleport, with Iceman, from Prague to Egypt. That may just be a bad transition, and his powers may have changed lately, but still. Well, at least Nightcrawler is still making appearances; I'm going to look on the bright side here.