David Alan Landers, who was also known as "Mastodon," was one of the main characters in D.P.7, a comic book series set in the "New Universe," part of a new imprint of comics published by Marvel beginning in 1986. Mastodon was seen in a few other comics that crossed over with "New Universe" titles, including mainstream Marvel universe titles such as Exiles.
Dave Landers, according to his biography published in the original D.P.7 series, was raised as a Lutheran but was an atheist as an adult.
From: "Dave Landers" page on "The Appendix to the Official Handbook of the Marvel Universe" website (http://www.marvunapp.com/Appendix/lnders.htm; viewed 11 June 2007):
Real Name: David Alan Landers
Place of Birth: Oshkosh, Wisconsin
Religion: Raised Lutheran, now atheist
First Appearance: DP7 #1 (November, 1986)
From: "Atheist representation on the Avengers" forum discussion started 20 June 2001 on "Comic Boards" website (http://www.comicboards.com/avengers/view.php?rpl=010620155126; viewed 11 June 2007):
Posted by Jae on Wednesday, June 20 2001 at 11:07:15 GMT
Atheist representation on the Avengers
The teams pretty well rounded now, but are there any atheistic members?...
Posted by Prime Eternal on Wednesday, June 20 2001 at 15:51:26 GMT
[Mark] Gruenwald [i.e., the writer of Quasar and DP7] also had an atheist character -- Dave Landers-- in his DP7 series. Probably the best issue of DP7 was #5, when the characters went to an exorcist to see if he could remove their powers. Throughout the series, Dave's frienship with Randy O'Brien (a Catholic) was the most compelling feature of the book.