Crossworlds by Krishna Rao

5.10

College good guy Joe is drawn into a battle to save the world from arch-enemy Ferris. Joe's heirloom pendant just happens to be the key to the staff that opens doors to the Crossworlds. When Laura shows up to check on the key and Ferris' goons begin their assaults, they run to semi-retired adventurer A.T. for help and guidance.