John Carter needs no armor!!!!
John Carter of Mars has been said to be seminal (Google says that word means “a work, event, moment, or figure that strongly influencing later developments”. Take that as you will…) series in science fiction, and one of the shining stars of the planetary romance genre and pulp era. I don't think that applause is off base. For me, it stands as a distinct type of adventure, and is one of the best I read.
More importantly than that, they are great novels, full of action, romance, sexism, possibly some racism, violence, nakedness, more violence, honor, righteousness , weak vulnerable females, strong lethal females, and people-that-can-detach-their-heads-from-their-bodies.
As such, the books are both a great inspiration, and a dangerous inspiration to GMs and players the worlds over.
This book applies to:
D&D, Pathfinder and sundry
2nd ed D&D's Spelljammer setting
Classic World of Darkness (very mildly)