That yellowish tinge to my face is not jaundice but egg yolk. For years I’ve been blathering about how important a development it was when, in 1968, six Marvel super-hero strips finally escaped the confines of the split books (Strange Tales, Tales of Suspense, and Tales to Astonish) and earned their own titles (Captain America, Iron Man, Incredible Hulk, Sub-Mariner, Dr. Strange, and Nick Fury, Agent of S.H.I.E.L.D.). Two other characters (Captain Marvel and the Silver Surfer) also got their own books for the first time, and I mentioned that Smiley dubbed this epoch “Phase Two” in one of his “Stan Lee’s Soapbox” editorials.
Except he didn’t. Tonight, while perusing the reprint of Amazing Spider-Man #52 in Marvel Tales #37, I stumbled across Stan’s “Super-Special Announcement” about Phase Two…in September 1972. What, if anything, his official nomenclature was for what I THOUGHT was Phase Two, I obviously have no idea at the moment, but this was something different. I’ll boil it down for ya, because by his own admission, Stan is “the kinda guy who can’t say ‘hello’ without making it a speech.” (Kindred spirits?)
He begins by enumerating some of Marvel’s prior innovations: “heroes with human hang-ups,” guest-star appearances, continued stories, the Bullpen Bulletins page, and crediting the creators. Phase Two is characterized, first, by several promotions, including that of Roy Thomas to Editor, in which capacity he will oversee such writers as Gerry Conway, Archie Goodwin, Steve Englehart, and the unrelated Mike and Gary Friedrich. Frank Giacoia becomes Assistant Art Director, while Stan himself–now “unleashed”–will be free to tackle all sorts of new projects and directions.
Finally, he mentions that they are in the process of launching a whole new line of titles, and it is this next major expansion that interests me the most. I recently opined, in fact, that the very year of his announcement, 1972, might just have been Marvel’s most exciting annum, and since I now know that this is what he meant by Phase Two, it’s not too surprising. Many of them were admittedly short-lived, but here is just a sample of the exciting events; can’t wait to start covering them over at Marvel University…on or about July 17, 2013! 
- Debut of Werewolf by Night strip in Marvel Spotlight #2
- Debut of Beast strip in Amazing Adventures #11
- Marvel Team-Up #1
- Debut of Warlock strip in Marvel Premiere #1
- Tomb of Dracula #1
- Luke Cage, Hero for Hire #1
- Debut of revived Ant-Man strip in Marvel Feature #4
- Debut of revived Dr. Strange strip in Marvel Premiere #3
- Defenders #1
- Debut of Ghost Rider strip in Marvel Spotlight #5
- Captain Marvel resumes publication with #22 (first issue since 8/70; Starlin imminent)
- Debut of Man-Thing strip in Fear #10
Mind you, that’s an average of one new or revived strip/book per month, and I’m not even including the likes of Night Nurse!
I always forget: did Luke Cage debut in his own mag or did he appear somewhere else first?
I believe the most important part of Phase Two was, surely, the return of Ant-Man. Was there ever a… tinier… superhero?
Luke Cage’s first appearance was Hero For Hire #1.
Was waiting for you to razz me on Mr. Pym (although, as I recall, that brief Marvel Feature run had some points of merit). Thank you for not disappointing me, and for beating me to the punch in answering Tom’s question.