Dungeons and Dragons (1983)

The kids are sent to a valley where a village of gnomes reside. However, the gnomes are enslaved by Venger to mine the mystic gems out of the walls of the valley. When the kids attempt to free the people, they are informed that the residents cannot be free until Lukion, the gnome spellbinder, lifts the spell upon the valley. The kids then set out for the Swamp of Sorrow to find Lukion, and free the prisoner trapped in a prison without walls.