Soulcasters are individuals in the Stormlight Archive series by Brandon Sanderson who possess the unique ability to manipulate the fundamental forces of nature using magical gemstones. They can summon and control various elements, such as fire, water, and stone, by channeling their powers through these gemstones, which are often infused with the energy of the sprens. The practice of soulcasting requires skill and concentration, as it involves transforming one material into another. This ability is highly valued in the world of Roshar, where soulcasters play crucial roles in society, from crafting materials to aiding in warfare and healing.