Ruin

Also known as dungeons, Ruins are in game structures that house difficult enemies and valuable loot. Each ruin will have a specific format that is unique to the biome it's present in, and the creatures inside are much more difficult than their normal counterparts. The primary reason to explore these dungeons are the chests that are scattered around their interiors, and can drop some of the most important items a player can create. They also have unique drops that can not be found anywhere else, and the higher tier ruins will have better quality weapons and armor as well.

Ruins are not biomes in of themselves, but each ruin will always be found within one or two associated parent biomes. The ruins do not seem to directly be named in-game, but their component blocks are therefore all of the ruins have been named after their blocks for this Wiki.