Dungeon Ruin

The Dungeon Ruin is a type of ruin which can be found just below the surface of the Swamp Biome. Because they are usually buried, they are most easily spotted when they are partially exposed by nearby cave systems or Rivers. Their outer appearance is that of a simple, rectangular building comprised of pale stone, but they extend much deeper down then hinted at by what is usually exposed. Dungeon ruins are comprised of Dungeon Ruins Cubes.

Overview
While all ruins are also thought of as "dungeons", Dungeon Ruins are true dungeons in the more literal sense. They have inner the appearance of an old medieval prison complete with prison cells and torture chambers. Their halls are patrolled by Zombie and Plague Zombie. The boss of the ruin is a single Elite Toxic Zombie.