The Darkside is coming home. Third Battalion, 4th Marines, will return to their base at Twentynine Palms, Calif., next week following a trying seven-month deployment in Afghanistan. The unit saw heavy combat while patrolling The Upper Gereshk Valley and Nahr-e Saraj district, an area of northern Helmand province just south of volatile Sangin district. Five* members of the battalion died and dozens more were wounded during the deployment, Marine officials said in a news release announcing the unit’s return to California. They handed over control of the area to a joint Afghan-British force headed by 42 Commando, a Royal Marine…