In the Dungeons & Dragons fantasy role-playing game, the Spirit of the Land is a fey. They inhabit certain geographic areas, and lie in invisible dormancy until they feel the area they guard is threatened, in which case they rise to defend it. Originally appearing in the Dark Sun campaign setting, they have since been reintroduced to 3rd edition D&D, along with several other creatures from Dark Sun, in the Monster Manual II.
Spirits of the Land, in their natural form, are invisible and intangible. When it wishes to be seen it can manifest as a humanoid, animal, or elemental of its own size and composed of one particular element. The illustration of one in the Monster Manual II shows it in the form of a bear made out of wood and earth.
There is little to say of the society of a Spirit in the Land that has not already been said in the introduction. They lie dormant, as one with the land, in certain geographical areas, and arise to fight when they feel the area they guard is in danger.