New X-Men #140

Part two of "Murder at the Mansion" arrives with a cover that lays out the sprawling Xavier Institute cast in striking fashion — dozens of mutant faces, from the bald-domed Professor X and visor-wearing Cyclops to Beast, Storm, Emma Frost, Nightcrawler, Iceman, and many more, arranged within a glowing gold X-Men emblem against a stark black background. Phil Jimenez's cover pencils and inks give each portrait real personality, making the sheer depth of this world immediately apparent. With Grant Morrison writing and Jimenez on interior art, this 2003 mystery arc is the kind of ensemble-driven storytelling that reminds you just how rich the X-Men's world truly is.