The Apocalypse Ark (#6), softback adventure for Mutant Crawl Classics, by Brendan J. LaSalle
“The Ancients called it Beta Collection Unit NC-787.
Its mission – to find, collect, and categorize animals and plants, record their DNA, and when required, strip invasive mutant DNA from extant creatures to create genetically pure stock. Then the Great Disaster came. Beta Collection Unit NC-787 sat dead and inert for ages while the world evolved around it for thousands of years.
When stories of a rogue “smart metal” being the size of a mountain come to your village, no one takes them seriously, at least until the treaded 10-story-tall monstrosity begins cutting a gigantic swath through your hothouse jungle homeland. Invulnerable to even the mightiest mutations, your only hope to stop its menacing march is to find entry to its interior and access its power sources and sinister inhabitants.”