Synergy enables you to play through the Half-Life 2 series and many other singleplayer Source Mods cooperatively with friends.

Guides
Synergy – Guide to All Trucks/Vans on Highway 17
A guide detailing all of the locations where you can find the trucks/vans in highway 17. All Trucks/Vans on Highway 17 D2_coast01 Truck + van next to the first house […]