A+X 13-18 are yet to be placed, right?
I haven't read them yet, but I'll try to do it in this week and write here some pointers to maybe help out on their placement
Edit:
My notes on A+X 13-18
Disclaimer: I'm not well-informed in anything other than the X-Men books
- The 6-parter that runs from 13 to 18 involves Cap. America & Cyclops hunting down Cadre K.
It has appearances from Emma Frost, Stepford Cuckoos, Tempus, Ant-Man & Dr. Doom.
One of the Cuckoos has black hair, which places this story after UX3 9
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- Issue 13: Emma Frost & Black Widow track down someone who has Emma's sextape
Imo, it can be placed on either side of the 6-parter above
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- Issue 14: Magneto & Spider-Man (Octopus) try to rescue a mutant boy from M.O.D.O.K.
Imo, it can be placed on either side of the 6-parter above
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- Issue 15: Beast & Doctor Strange Vs Impossible Man
Imo, it can be placed on either side of the 6-parter above
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- Issue 16: Spiderman helps Psylocke fight some gangsters and Psylocke becomes gravely injured
This one occurs in the past, back in the 90s. It shows the X-Men's blue team picking up Psylocke. It should be placed somewhere where there's a considerable gap in time between Psylocke appearances as she is injured in this story. X-Men wise, it must be placed after X 1-3 (start of Blue/Gold teams) and before Fatal Attractions (Wolverine leaves the team). I think that placing it immediately after X 1-3 would work fine (dunno about Spider-Man though).
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Issue 17: Broo spends a day with Iron Man.
Iron Man has the black armor. There are also appearances by Beast & Nova
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Issue 18: Murderworld gains sentience and kidnaps Shadowcat & Vision
Imo, it can be placed on either side of the 6-parter above
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I think that all of these issues should be placed before Infinity, as some stories touch intergalactic themes, like the 6-parter with the Skrulls, Broo's day with Iron Man, etc and none mention Infinity.
X-Men wise, I would lump everything (except the Spider-Man/Psylocke team-up) together maybe before Battle of the Atom.