There are no Zombies or additional NPC's apart from the scientists & animals, so players can explore & build freely. PVE is scheduled between Sunday, 24:00 hours CET till Friday, 17:00 CET. During this period, players will not be able to harm other players/bases or raid other players. 

Schedule for PVP is from Friday, 17:00 CET till Sunday, 24:00 hours. Raiding and killing/looting other playersis allowed during PVP (See PVP Rules page).