There's a few things I was sure were going to make my list as I did my initial brainstorm, but wound up on the outside looking in.

The two biggest I thought would make it were the Usagi Yojimbo/Leonardo or Usagi/TMNT x-overs, but it had been a while since I read either and I never got around to revisiting them to compose my thoughts as to why I liked them, so they got left off.

The other was a pair of Conan crossovers, the two part Elric story in Conan the Barbarian #14-15 and the Song of Red Sonja in CTB #23 (her first app as a cameo) & 24. I am not really a fan of Conan cross-overs, I prefer the purity of vision of the original Howard stories, and I felt the Sonja story better fir that than the Elric story, but when it came down to making final choices that one was left out as well.

The rest of my list is stories featuring favorite characters I thought of and it was just a matter of trimming it down to those that could fit in the 12. The characters I wanted to feature were: The Spirit, Planetary, Dr. Fate, Phantom Stranger, Spectre, Green Arrow, Zatanna and Madame Xanadu. Most got on their accompanied by Batman, but not all. Comics featuring those that didn't quite make the cut bit which got serious consideration...

The Phantom Stranger/Deadman story from DC Super Stars 18 which is another Rutlan/Tom Fagan story.
The Spectre/Flash team up form B&B 72
The Batman/Spectre team up from B&B 75
The Dr. Fate/Hourman team ups form Showcase 55-56.

There were two Marvel features that were on my radar-The team up of Ulysses Bloodstone and Dr. Druid form Marvel Universe 4-7 but the Monster Hunters became an actual pseudo-team, so I wasn't sure it would qualify, and Dr. Strange/Dr. Doom Triumph and Torment, but Doom is a villain and I wanted to avoid villain team ups for reasons.

There were others I checked out or briefly thought of, but they didn't get serious consideration. And there were a few that others posted I was like, wow I should have thought of that one, but I hadn't and I was sticking with what I came up with.

-M

I thought of other silly ones like Spider-Man and SNL's "Not Ready for Prime Time Players" from Marvel Team-Up #74, with creditable likenesses drawn by Bob Hall and Marie Severin (and written by Chris Claremont):



Or The Avengers' B-list facing a deranged inventor on the David Letterman Show in The Avengers #239 by Stern, Milgrom, and Sinnott.



I already had a few John Byrne appearances in my list, so I didn't press the limits of the contest by seeing whether She-Hulk crossing into Elfquest counted (Wendy and Richard Pini, from two guest pages in Byrne's Sensational She-Hulk #50):



Or the original Bulletgirl berating sexy new Bulleteer in Bulleteer #3 by Grant Morrison and Yanick Paquette:



I included Cerebus' encounter with Moon Knight (well, Moon Roach) and mentioned his previous meeting with Wendy Pini and Frank Thorne in their characters of "Red Sonja and the Wizard."




Dave Sim's art looked so much better by the time he got to the High Society arc. Here's footage of Pini and Thorne in-character from 1978.

Several of my near misses already came up in the individual threads, e.g. :

Batman and Swamp Thing by Wein and Wrightson
Hercules and Thor by Lee and Kirby
Thor and the Silver Surfer, byLee and Buscema
Etc

Here are a few others that come to mind (don't have my long list on this device so I'll probably forget a few):

Silver Surfer and Dracula by Wolfman and Colan in ToD
Conan and um, er ... the 20th Century? By Thomas and Buscema in What If
Dr. Strange and Dracula in ToD and Dr. Strange by Englehart, Wolfman, Colan
Black Panther and the FF by Lee and Kirby in FF #53,54(?)
Black Panther and Daredevil by Thomas and Colan in DD #60-something
...

will add more as I remember them

These are some of my long list-



The B@B is one of my favorite stories , and again by Alan Brennert. I used it a few years back in a TDOCC and didn't want to repeat it and also maybe Batman and Robin would have been disqualified. The FF issue amounts to being just a punch up but it was my first Hulk Thing battle, so it holds a special place in my heart.

Both of these Hitman books were fun. They just don't make the cut as I already used the Batman/Hitman arc as one of my picks.

I tried to stick to pair-ups, except for Wonder Woman/Fafhrd and the Gray Mouser. And I swapped a few out that had already gotten good coverage, although I felt I had to include Deadman and Kara, a genuine classic (although one that could have been even stronger with a better art job than Dick Giordano's rather stiff rendition). I intended to avoid leaning heavily on B&B, which (for reasons you might have already guessed!) I've been studying pretty carefully for over a year now. But as a big Jim Aparo fan, I did decide to give him a place in all my top few spots, including some B&B issues.

Some my near-misses that didn't crop up in anyone's list (that I noticed):
Batman and The Atom in B&B #115, "The Corpse That Wouldn't Die", in which the Atom animated a comatose Batman from inside his brain to solve what he thought would be the Batman's final case! B&B 100 is a strong contender, but again, I wanted to go with our leader's original intent, and this 5-way team-up seemed too crowded for this contest.
I seriously contemplated the surprising team-up of The Creeper and Wildcat from Super-Team Family #2. It wasn't a very good story, but it represented a promise of potential surprises, too few of which would ever materialize. But c'mon, if they can publish a team-up of these two, what couldn't they surprise us with?!
DC's Shadow #11, guest-starring the Avenger, was a team-up of my two favorite pulp characters. I thought of this one too late for my list, but the weakness of the Cruz artwork (in comparison with Kaluta and Robbins) would probably have kept it off my list anyway.
I had more Marvel entries than I originally expected to, none of them from the usual suspects (MTIO, MTU, G-S S-M).
Dracula and the Silver Surfer in Tomb of Dracula #50 is one Marvel comic that I considered early on, a crossover that worked way better than I think anyone would have expected.
Fin Fang Foom wasn't quite enough of a solo star to make me feel comfortable including his encounter with It! The Living Colossus, but man, do I love all four issues of that run in Astonishing Tales!

I was disappointed that no one picked Jerry Lewis and Batman or Jimmy Olsen and Don Rickles!

Another two part Bryne Team-up story. I confess that I don't remember the story but I really like Hank and Janet , even outside of the Avengers book.

The Deathstroke book just narrowly missed being in the 12. Batman and Stroke battle and Batman gets destroyed. The 4 part story had to do with finding a States witness before he was killed and they both team up in the end.