Virus is a microscopic organism that lives in a cell of another living thing. Although viruses are extremely small and simple, they are a major cause of disease. Some viruses infect human beings with such diseases as measles, influenza, and the common cold.
Passive Mobs. Passive mobs are composed of creatures that will never, under any circumstances, attack the player. Some passive mobs can be bred to create more of them, e.g. pigs can be bred to effectively farm them.
Most mobs can be tamed in various ways, such as catching aquatic mobs (like fish or crabs) with a fish net or by hatching mob eggs such as wyvern, ostrich, many types of fish, Komodo dragon or shark eggs.