An ancient people built mystical fortresses made of melted stone; from the wall’s these fortresses defenders appeared to burn with a powerful energy and strike at their opponents with a supernatural force. Today most of these forts are abandoned and the art that made them lost.
Rain slowly builds, thunder and lightning continue to roll in. Road muddies, horse/wagon getting stuck in the mud. Thunder strikes coinciding with a deep hole a horse just walked in, horse panics, breaks its leg (maybe just sprain?). Horse is decompacitated and the rain just went from pouring to an all out monsoon. Shelter needs to be found, horse needs to be taken care of, covered in mud, add the posibility of items being lost to the confusion with the wind and dealing with spooked animals.