This is a list of all the plotlines and other information given to the reader which, for one reason or another, have not been resolved. This format is more or less cribbed from Paul O'Brien's V9.2 X-Men Danglers List (those titles have exponentially more danglers than a book like IM and its spinoffs) and has tried to adhere to his definitions of "Danglers", i.e. a Dangler is a deliberately created plot, which is not referred to later for at least some time.
So what is a dangler? Well, they tend to come in one of three ways. Firstly, there's plots that were started and never resolved. The classic example is the "What's the deal with Deathcry" dangler. Secondly, there's plots resolved in such a way as to make it clear that they will be reopened. "Where will the Forever Crystal turn up next?" is one of those. Thirdly, there's lines of dialogue that refer to past events that haven't been shown yet, but I'm unaware of any such open danglers for the Avengers. I'm sure you all know a few like that, tho'.
While reading, keep in mind that only in-story explanations really resolve danglers. Danglers are referenced by the relevant issue(s) whenever possible, but some are just general hanging questions.
This Dangler list was first compiled by my friend, Omar Karindu on The Avengers Message Board, and has been added to by myself, comico, merc, Kurt Busiek, Ben Herman, Century: Your Alien Hero, Ian Watson, Pgunn, Fin Fang Foom, piper, Ralf Haring, Peter Luzifer, Somebody, TJ Burns, Snood, Per Degaton and Dermie.
Iron Man Danglers
Got a dangler I don't? Give me a shout at firstname.lastname@example.org.
09/12/04- Updated Iron Man Part I.
01/18/04- Added Vol. I #151 to Avengers Part II.
11/17/03- Added Iron Man Danglers!
11/20/02- Vol. I #16 added to Part I; Vol. I #88 added to Part II; West Coast Avengers Vol. I #3 added to Part IV.
11/02/02- Vol. I #14, 15, 19, 24, 38, 53, 55, 84, 111, 187, 269, 386, Avengers Annual #2, 10, West Coast Avengers Vol. II #28, Avengers Unplugged #5, Solo Avengers #11, and Tales Of Suspense #59 added to Part I; Vol. I #2, 23, 28, 30, 101, 225, 363, 395, 397, 399, 401, added to Part II; Force Works #1, 17 added to Part IV; Avengers Unplugged #6 added to Part V.