As Dr. Gordon Freeman, you were last seen exiting City 17 with Alyx Vance as the Citadel erupted amidst a storm of unknown proportions. In Episode Two, you must battle and race against Combine forces as you traverse the White Forest to deliver a crucial information packet stolen from the Citadel to an enclave of fellow resistance scientists.
FGD for Black Mesa Source use in valve hammer editor (Source SDK)
how do I add this to the hammer editer?