Spirits are sentient beings originating from the metaplanes. Under some circumstances, they can cross the gap between their dimension and ours. A lot of magical tradition manage to invoke a specific set of spirits.
- Shamans and Druids invoke Nature Spirits
- Toxic Shamans invoke Toxic Spirits
- Insect Shamans invoke specific Insect Spirits (cf, Chicago, and Bug City)
- Hermetic magicians invoke Elementals
- Wuxen invoke Spirits of the Elements
- High ranks Tír na nÓg followers of the wheel are rumored to invoke the Wild Hunt
...
Some spirits, however, don't need the commands of a magic user in order to come into our world:
- Baba Yaga
- Bean Sidhe
- Brocken Bow
- Corpselight also known as the willowisp
- Domovoi
- Free Spirit
- Ghost
- Apparition
- Specter
- Man of the Woods
- Nomad Spirit
- Salamander
- Tungak
- Wild Hunt
- Wraith
...