Dynamite isn't the first comic publisher to inject sci-fi/fantasy elements...
...into this usually "realistic" high adventure strip!
Written and laid-out by Bhob Stewart, pencilled by Steve Ditko, and inked by Wally Wood. this cover-featured story from Charlton's Jungle Jim #22 (1969) was prepared for the character's previous publisher, King Comics, but ended up at Charlton when King Features Syndicate dropped in-house comic book publishing.
You can read Bhob's account of how this story was produced HERE.