This happened to me a single male zombie one hit killed me. I know it was a zombie because I had just checked the player list and everyone else had logged out leaving me alone on the server. My entire inventory was in pristine condition as I had just completed upgrading every item in my pack. 15 day survivor, all pristine gear, one hit... "YOU ARE DEAD" LOL! I was in crouched position behind a bush, heard the zombie, stood up, saw him in front of me, raised weapon, took aim, lights out! WTF? Me not the zombie!