Orc spiritspeakers use a shamanistic connection through the earth to communicate with the hidden, ethereal creatures of Mennara. This not only allows them to speak as mediums for The Unseen, but also to act as conduits for the spirits to act on the mundane world.
Whether attached to objects or locations, minor spirits are normally unable to summon the energy or focus it takes to act on the physical world. However, through a combination of natural ability and rigorous training, spiritspeakers can thin the barriers that surround Mennara enough to allow apparitions to manifest. That lets benevolent sprites openly share their wisdom, guardian spirits to physically defend their territories, and wraiths to directly attack whoever holds their cursed object.
That connection also gives spiritspeakers a supernatural edge in combat and adventuring, as many will have gathered a modest assortment of objects with useful entities attached which can be summoned for aid or protection.
References
- Realms of Terrinoth