At first, designer Scott Modrzynski had the idea to draw all the X-Men as X-shaped icons. Sources disagree on their exact number over the 48-year run of the first volume of Marvel's mutant flagship, but it's around, if not more than 100.
But as Modrzynski kept drawing these little X designs, his obsession deepened. Here then, are 2,535 characters — basically everyone who wasn't some mute bystander — who appeared in the 544 issues of The Uncanny X-Men from 1963 to 2011.
It took Modrzynski two years to do this, which he titles Unnecessarily X-essive.
"I kept crossing, erasing and redrawing the line as I got deeper into this project," said Modrzynski, an artist who keeps the lights on with a job in advertising. "First it was just X-Men. Then X-Men and villains. I knew I'd have to add allies like Stevie Hunter who fall into neither category, and the rabbit hole grew deeper."
The standard for inclusion is basically, "Anyone who speaks in the comic." Modrzynski said. "This is typically the random 'aw shucks' civilians and the "Kill the Mutie!" bigots, but really anyone in the book counts."
The icons appear in chronological order, so while you can't Ctrl-F for someone by text, if you know the issue number of their first appearance in X-Men (the Marvel Database helps out tremendously) you can scroll into the neighborhood and find them. This is how, for example, I found Lockheed, Kitty Pryde's pet dragon (X-Men No. 168). yes, he is here. And Madelyne Pryor in the Dark Phoenix costume in the seminal X-Men No. 175, which got me hooked on the series in the early 1980s.
And then, as if Modrzynski was trying to prove the comprehensiveness of this endeavor to me and to me only, is the bartender at Monahan's — with the "DON'T BOTHER THE BARTENDER" shirt — from X-Men No. 183, when Wolverine and Nightcrawler take Colossus out to get beaten up by Juggernaut for breaking up with Kitty.
Costume redesigns, cameos (Stan Lee is in here twice), Modrzyznski's work has value not only as a piece of scroll-through art, it's also a legitimate catalog of X-Men character history and uniform design. (And because X-Men ran for nearly 50 years, and was so crossover-heavy in its early life, just about any Marvel hero or villain of note is in here.)
Also, Modrzynski is selling individual icons as buttons for fans who spot their favorite and want to wear it with pride.