Brain-Child

Born from the celebrated Kurt Busiek and George Pérez run that revitalized Marvel's mightiest team, Brain-Child made their debut in Avengers #10 (1998) and has kept genuinely rarefied company — sharing pages with Iron Man, T'Challa, Scarlet Witch, and Wanda Maximoff. Though appearances in the catalog are select rather than sprawling, the character's place in a landmark Modern Age Avengers era gives them a collector's cachet that punches well above their page count. If you're digging into the Busiek/Pérez run — one of the most beloved in the title's history — Brain-Child is one of those intriguing figures worth tracking down.