Nisse
Nisse (Swedish tomte, tomtenisse, tomtegubbe) is the Swedish household spirit: small, grey-clad, red-capped, dwelling under farmstead floorboards. Protects livestock, harvests, carpentry; expects Christmas porridge with butter. If neglected, turns vengeful: kills livestock, breaks tools, leaves farm. Shapeshifts (goat, horse). Origin: ancestral ghost of farm-clearer + nature spirit (tomtevätte).