Commandos are elite versions of assault units. They use SMLAV & SMLAP shoulder-mounted mini-mortars which come in an anti-personnel version (which functions like a mortar, with high blast radius and infantry damage, but low vehicular damage) and anti-armor (with high damage to vehicles and infantry, but smaller blast size). They come equipped with assault rifles and generally have higher health than other classes.
Duke is a Commando Leader of The Ghosts who fought against Yuri Treskayev.