These are monsters that appear in the stone layer located deep underground.
“Armored Skeletons are Hard Mode enemies found underground, largely (but not entirely) replacing...Armored Skeleton
“The Spectral Elemental is a monster found only on the Console Version in the Underground Hallow...Spectral Elemental
Pages in category "Underground Monsters (Stone Layer)"
The following 17 pages are in this category, out of 17 total.