An update to the SpaceTraveler Solar System & Space Missions Simulator at BINARY SPACE now includes the OSIRIS-REx mission to the asteroid Bennu, which just launched this month. (See the posting OSIRIS-REx to return sample of asteroid Bennu.)
Note that SpaceTraveler is not a game type of simulator but an educational tool to investigate the flights of actual spacecraft missions via their orbital trajectory and maneuvering data.