Once the initial hordes have been driven off, Lieutenant Sheng will inform Alpha Company that the rest of his team, including his two Corpsmen were separated during the chaos and have rallied at the Armory. The team must then head there to regroup and combine their forces.
This section of the campaign has no time limit and offers a good opportunity to search for weapons and other gear. Players should also try to kill as many Infestors as they can for the early levels. When the team feels they are ready, proceed to the Armory. Be wary in stalling too long during the part, the team may end up using too much ammunition and find themselves in trouble during later stages.