“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.”
Zombies are common in the Overworld at light levels of 7 or less. They can also spawn from spawners inside Dungeons.
If a Zombie kills a Villager/Baby 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/Baby Zombie. Baby Zombies can fit through 1 block holes, are faster than regular Zombies and do not burn in the sunlight. They can also ride Chickens (very rare).
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