Half-Life 2 Episode Two - Under the Radar Walkthrough
While Alyx and the rebels work on the car, Gordon disables the Combine Autogun of the The Junk Yard blocking the road. The rebel technician installs a radar detector that picks up Resistance caches. They travel through the zombie-infested countryside and retrieve supplies from several hidden caches.
An enormous Combine ambush is laid for them at the White Forest Inn, but after defeating Hunters, soldiers, and Elites they approach the White Forest base. They witness a dropship being downed by rebels, however the Strider that it was carrying awakens. Dog arrives and defeats the Strider, and Alyx challenges him to a race to the base.