If you are looking for the "latest" version with all available content, the game's development concluded in 2018 with several major DLCs:
The game follows the story of the New Kid, a young boy who moves to South Park and joins the boys Cartman, Kyle, Stan, Kenny, and Butters on a series of adventures. The gameplay involves exploring the town of South Park, completing quests, and engaging in turn-based combat. If you are looking for the "latest" version