Deaths
You live in a world with many dangers, ruins, artifacts, etc. One significant dangers are Deaths. Deaths will ravage the entire world in search of players to kill. Not only will they kill players, but they will also kill all other mobs, including villagers, hostile, passive, or other. Deaths are extremely fast, but not very smart. They have slow reaction times and aren't very agile. However, they do a lot of damage and are hard to hit. In my opinion, the easiest way to kill a death is with a gun, preferably a shotgun. Keep in mind, Deaths are one of the rarest things in the game.