Abandoned Mineshaft

Abandoned mineshafts are structures that will generate in all Overworld biomes. They consist of a series of winding corridors, rooms that branch off in a series of other corridors, and broken up sections of rails on the floor. If a corridor generates in midair, it will generate with a series of chains connecting it to the ceiling.

A variant of mineshaft, the badlands mineshafts, will generate in badlands biomes. The regular mineshaft is built up with oak wood, but the badlands mineshaft will consist of dark oak, a dark brown wood type.

These structures contain cave spider spawners, which will spawn the poisonous variant of spider. The area around these spawners will be packed with cobwebs. Cobwebs, when walked through, will greatly slow the movement of players and mobs, but will not affect the cave spiders.

The structure will contain a series of loot chests, in the form of chest minecarts. The more common loot items in these chests are rails, name tags, glow berries, and the occasional golden apple. There might also be an assortment of seeds. Rarely, you will find diamonds, and, even more rarely, enchanted golden apples.