I was playing a multiplayer game that my friend was hosting. We don't have any mods. The frozen lumberjack zombies showed up in the desert. A bunch of them. We decided to try a new game that I started. Again, no mods. I was started in the lush area with trees by the house that's near the snow biome. He was sent to start out in the fire biome. Masses of zombies went after him right away. Dogs, dire wolves, bears, and lots of zombies all within a few minutes of starting. I went into the nearby house and did the initial quests up to the point where I had to go to the trader. I decided to wait for the next day and was chilling in the upstairs room when all of a sudden a frozen lumberjack zombie came crashing into the house after me. I had never seen a frozen lumberjack around the forested biome before. The difficulty settings were adventurer. I don't know if that makes a difference, but we've never seen the frozen big guy outside of the snow biome before.