Kitsune

Most human think Kitsune don't really exist and it is all old folks tales, but in truth, they do exist in the Woods of the Marshlands. Kitsune are Spirits of the forest able to shapeshift into Humans or Elves. Some say they appear in places where nature is in good condition and the roots of the trees grow deep into the soil. The rarely leave the forests and venture through the human territory.
Even though Kitsune are curious beings they like to observe in distance. They always stay in a group and walk as a group, never will they leave one of them behind. When elves were still around, they used to be supporters for their works with nature, helped them to build cities with nature instead of bending nature to their will. In times of war, Kitsune were trained for assassination, spying and sabotage they almost never were in direct battle. But the wars the elves fought are forgotten like the existence of the Spirits of the woods.
By far they weren't the only forest spirits that helped the elves just one of many.