The Apocalypse Ark

From the publisher's blurb: A level 6 adventure for Mutant Crawl Classics RPG! 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. A rolling dungeon.