Posted March 18, 2016
stinkysack: The support person who told me LAN was not supported jumped into another thread I posted in and confirmed he was wrong and LAN is supported. I would post the link to that thread but GOG wont allow me for some reason. Its the "Multiplayer only available for GOG Galaxy users" thread
There you go: https://www.gog.com/forum/dying_light/multiplayer_only_available_for_gog_galaxy_users/post6