Living Jars are creatures from Elden Ring. They are large, seemingly innocuous, clay jars or pots with arms and legs. They range from slightly smaller than a human to towering in size. Inside their bodies are the fermenting flesh of the dead, and they seem to gain power from corpses they stuff themselves with.
In the Shadow of the Erdtree DLC, a different method of creating Living Jars is practiced by the hornsent, who force tortured, dismembered, and still-living prisoners into them (along with a single shaman/miko), where they fuse together as maddened amalgamations of their former selves.
Iron Fist Alexander and Jar Bairn are unique Living Jars.