“Zombies are the most common hostile mobs. They spawn in dark or dimly lit areas, and will attack the player by slowly moving toward them and inflicting damage by making contact. Like Skeletons, Zombies catch fire in sunlight. Zombies can be heard making roaring, moaning and growling noises when near. Also zombies are damaged by health potions.”
5% of all Zombies, which are common in the Overworld at light levels of 7 or less, are Zombie Villagers. If a Zombie kills a Villager, it has a chance (100% when on Hard difficulty, 50% on Normal, 0% on Easy) that the Villager will turn into a Zombie Villager.
Zombie Villagers can be cured by throwing a Splash Potion of Weakness at them, then feeding them a Golden Apple by right-clicking on the Zombie Villager with it. It will take 5 minutes before they turn into a Villager again.
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