Ninja Pigmen are Passive mobs that you can tame by giving them a sword. When you attack a mob with a tamed Ninja Pigman, the Ninja Pigman starts violently attacking the mob.
Ninja Pigmen also tend to become more aggressive and impatient over time if not given a sword, and can become deadly if they become to impatient with the player.
Further more, they will only except iron swords, stone swords, or diamond swords, making it harder to get them a satisfied.
They do use the durability bar on their swords, so they will break after they use them enough. If you do not give them a sword after theirs breaks soon enough, they will become untamed and hostile and attack.
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