Captain Marvel (DC Comics) Comics" #21 (1941) introduced the Lieutenant Marvels: three other boys named "Billy Batson" who could also become adult superheroes. Captain Marvel, Jr., the alter-ego of disabled newsboy Freddy Freeman, debuted in "Whiz Comics" #25 (1941). Mary Marvel, alter-ego of Billy's twin sister Mary Batson, first appeared in "Captain Marvel Adventures" #18 (1942). In contrast to Captain Marvel and the Lieutenants, both Mary Marvel and Captain Marvel, Jr. remained kids in superhero form, and were given their own eponymous books in addition to appearing as the lead features in "Master Comics" and "Wow Comics", respectively. Captain Marvel, Captain Marvel Jr., and
Excalibur (comic book) Excalibur (comic book) Excalibur is the name of several comic book titles featuring the team Excalibur and published by Marvel Comics, beginning with the original "Excalibur" comic book series which debuted in 1988. "Excalibur"<nowiki>'</nowiki>s original creative team, writer Chris Claremont and artist/co-writer Alan Davis, incorporated elements of two Marvel properties: the X-Men and Captain Britain. The resulting superhero team Excalibur first gathered together in "Excalibur Special Edition" #1 (1988) and were soon featured in a monthly series. Davis left with "Excalibur" #24 (1990) and Claremont with "Excalibur" #34 (1991), leaving a number of various plot points unresolved before his departure.