Zombie

Zombies are common undead humanoid hostile mobs that spawn at night.

Naturally
In the Overworld, zombies spawn in groups of 4 at a light level of 7 or less. In desert biomes, all zombies exposed to the sky will have an 80% chance to be replaced by husks, a zombie variant. Zombies that are not husks have a 5% chance to spawn as a zombie villager while all zombie variants also have a 5% chance to spawn as a baby zombie type. Baby zombies have an additional 5% chance of spawning as a chicken jockey.

A normal zombie can spawn when a husk drowns in water.

Sieges
If a player is in a village with at least 10 doors and 20 villagers at midnight, up to 20 zombies may be spawned near the edge of the village regardless of light level or transparent blocks. It can happen in any biome, even if it is Mushroom Island. Zombies spawned as a part of a siege will always be normal zombies; zombie villagers or husks will never spawn as a part of a siege.

Monster spawners
Zombies can spawn from monster spawners inside dungeons.

Baby zombies


Baby zombies make up 5% of zombie spawns. They behave similar to regular zombies, with the following oddities:
 * They are 30% faster than the normal zombies, yet they have the same HP as normal zombies. This makes the baby zombies more dangerous than their bigger counterparts.
 * The noises they make are higher-pitched than normal zombie sound effects.
 * $$, they can ride:
 * Cows
 * Ocelots and Cats (LCE)
 * Wolves
 * Mooshrooms
 * Adult chickens
 * Pigs
 * Pandas
 * Sheep
 * Polar bears
 * Horses
 * Donkeys
 * Mules
 * Zombie horses (unused jockey variant)
 * Skeleton horses
 * Llamas
 * Adult zombies
 * Adult zombie villagers
 * Adult zombie pigmen
 * Adult husk
 * Adult drowned
 * Spiders
 * Cave spiders:
 * Will use the baby zombie speed instead of the mob speed.


 * If a baby zombie is riding a mob that is also rideable by a player, that mob will no longer be rideable by a player.
 * A baby zombie has a 15% chance to become a jockey when it tries attacking a villager, player, or golem.
 * Baby zombie villagers will turn into baby villagers if cured.
 * Worn armor shrinks to fit their body size.
 * They are able to fit through 1×1 block gaps.
 * They give 12 experience points when killed by the player or a tamed wolf instead of 5.
 * Unlike all other baby mobs in the game, they will stay as babies indefinitely, and never grow into "adult" zombies.
 * They have a decreased hitbox size.

Armed zombies


Along with skeletons, some zombies are capable of picking up dropped items. These zombies will automatically hold any item they come across (except that jack o'lanterns, mob heads, and pumpkins will be worn on their heads), but if those items happen to be armor, weapons or tools, the zombie will use them. If they encounter another similar item, they will pick it up and drop their previous item:


 * if the new item is armor or a sword and the old item was not (for example, zombies prefer swords to pickaxes, and helmets to pumpkins),
 * if both items are armor/swords and the new item is better damage-wise (reduces more damage for armor, or inflicts more damage for swords),
 * if both items are armor/swords with the same damage reduction/infliction, the new item has NBT tags while the old does not or the new item is more damaged than the old item, or
 * if both items are bows and the new item has NBT tags while the old does not.

Items dropped by mobs in exchange for another cannot be picked up by players or mobs for 10 game ticks (0.5 seconds, barring lag), but can be picked up by hoppers.



Armor worn by zombies is not damaged from most damage sources, which means it cannot "wear out" the way player armor does. Helmets (not blocks like pumpkins) on zombies can wear away and break if the zombie is exposed to daylight or has an anvil or other falling block dropped on its head. Zombies also have a natural armor rating of, which gives 1.6 - 4%/8% damage reduction from most sources.

Some zombies which can pick up items spawn already in possession of such items, and those items may also be enchanted. The chances of that event are listed below. Zombie villagers can also spawn naturally with armor, weapons or tools. If a zombie spawns wearing multiple pieces of armor, the armor will never be mismatched (i.e. all pieces will be made of the same material).

If a zombie does spawn with armor, the chances of specific armor are as follows:

The chances of it being of a particular material are:

Any zombie that spawns with equipment (picked-up items don't count) will give 1–3 extra experience points per item.

Drops
When they die, zombies drop:
 * 0–2.
 * Iron ingots, carrots and potatoes (0.8% chance each, 1.2% chance with Looting I, 1.5% chance with Looting II and 1.8% chance with Looting III).
 * A if it is killed by a charged creeper.
 * Any picked-up equipment has 100% chance of dropping and will drop with the same damage level it had when picked up.

Naturally-spawned equipment
A Zombie Has A 0.04% Chance To Spawn With Diamond Armor And A 0.02% Chance To Spawn A Diamond Armor Baby Zombie Chicken Jockey.
 * Zombies have an 8.5% chance of dropping their naturally-spawned equipment, and will drop it with a random durability. Each level of Looting will increase the chance 1 percentage point (11.5 % with Looting III).
 * Zombies have an 8.5% chance of dropping their naturally-spawned equipment, and will drop it with a random durability. Each level of Looting will increase the chance 1 percentage point (11.5 % with Looting III).
 * Zombies have an 8.5% chance of dropping their naturally-spawned equipment, and will drop it with a random durability. Each level of Looting will increase the chance 1 percentage point (11.5 % with Looting III).
 * Zombies have an 8.5% chance of dropping their naturally-spawned equipment, and will drop it with a random durability. Each level of Looting will increase the chance 1 percentage point (11.5 % with Looting III).
 * Zombies have an 8.5% chance of dropping their naturally-spawned equipment, and will drop it with a random durability. Each level of Looting will increase the chance 1 percentage point (11.5 % with Looting III).
 * Zombies have an 8.5% chance of dropping their naturally-spawned equipment, and will drop it with a random durability. Each level of Looting will increase the chance 1 percentage point (11.5 % with Looting III).

Experience
Adult zombies will drop 5 experience and an additional 1–3 experience per naturally-spawned equipment. Baby zombies will drop 12 experience.

Halloween
If a zombie wearing a pumpkin or jack o'lantern is killed using a weapon enchanted with Looting, there will be a chance equivalent to the level of Looting used to drop the pumpkin or jack o'lantern, up to a maximum of a 3% chance of a drop.

Attacking the player


Zombies spawn in groups of 4 and will pursue the player on sight from 40 blocks away, as opposed to 16 blocks in other hostile mobs. The detection range of zombies is reduced to half of their normal range (20 blocks) when the player is wearing a zombie mob head. Zombies will periodically make groaning sounds, which can be heard up to 16 blocks away. Zombies will attempt to avoid obstacles, including sheer cliffs and lava, and will try to find the shortest path towards the player. Unlike skeletons, zombies do not try to avoid being hit, and continue to pursue the player even when being attacked. Zombies can sometimes deal damage through a closed door, as shown in the picture to the right. Zombies will sink in water, which facilitates their transformation into drowned.

Burning under daylight
At dawn, generally when the sun is 15 degrees or more above the ground (that is, when the moon can no longer be seen), most zombies will catch fire and burn once exposed to direct sunlight. They won't burn if they're: Zombies may make some attempt to seek out shade during the day, or enter bodies of water to protect themselves from burning up, but will exit protective areas to chase a nearby player or villager.
 * in a sufficiently shaded area: a sunlight level of 11 or less;
 * in water;
 * or wearing head armor (but the armor will take damage).

If they attack an entity while burning, they may set it on fire, with a (30 × regional difficulty)% chance, and with a 2 × floor (regional difficulty) second duration. If wearing armor enchanted with Thorns while burning they may set players attacking them on fire with thorns damage alone.

Undead
Zombies are undead mobs, harmed by the status effect Healing, healed by the status effect Harming and are unaffected by Regeneration and Poison. The Wither will not attack Zombies. Affected by Smite Enchantment.

Picking up items
A zombie holding an item it picked up will not despawn when left alone. On easy mode, zombies have a 1% chance of picking up an item. On normal mode, zombies have a 7% chance and on hard, they have a 20% chance.

Attacking villagers


Zombies will attack villagers within 42 blocks, and they can always see villagers through walls. Once a zombie has focused on a villager, the zombie will ignore any other villagers and the player, until its target is dead or the zombie is attacked.

Breaking doors
Up to 14.5% of zombies (depending on regional difficulty) in pursuit of a target can bang on closed wooden doors, and on Hard (and Hardcore) difficulty can succeed in breaking them down. Otherwise, the door will crack, but not break. Iron doors are always safe.

Attacking iron golems
Zombies will attack iron golems within 42 blocks. Iron golems and snow golems will attack zombies without provocation.

Reinforcements
On all difficulty levels, damaged zombies will also call all other zombies within a 67×67×21 to 111×111×21 area centered on the attacked zombie to target the attacking player, like zombie pigmen.

On Hard difficulty, zombies can spawn additional zombies to “help” when damaged. Each zombie has a "likeliness to call reinforcements" statistic which ranges from 0–10%, and "leader" zombies (0–5% depending on regional difficulty) get a bonus of 50–75 percentage points to the stat. When the zombie is damaged by an entity or is damaged while targeting an entity, up to 50 attempts will be made to randomly choose a spawn location (0 or ±7–40 blocks away in all three axes) that is above a block with a solid top surface, has light level 9 or lower, has no players within 7 blocks, and has no colliding entities or blocks at which to spawn the reinforcement. Both the damaged zombie and the new zombie will have a 5 percentage point penalty to their "likeliness to call reinforcement" stat, preventing infinite zombies from spawning this way.

These effects can be negated by killing the zombie in as few hits as possible, by using environmental damage such as cactus or lava, or by avoiding them completely.

Attacking turtles
Zombies will attack baby turtles and actively seek out and destroy turtle eggs, by jumping on them until they crack and break.

Becoming drowned
If a zombie is in water, and not in a boat, for 30 seconds it will begin converting into a drowned. The zombie will start to shake, similar to a zombie villager being cured, and after 15 seconds the zombie will be converted to a drowned. Once this process starts, it cannot be stopped.

If the zombie is holding or wearing any items, the converted drowned will keep those items. In Bedrock Edition, an empty-handed zombie converted to drowned has a small chance of holding a nautilus shell or a trident after conversion.

Only normal zombies can become drowned, zombie villagers and husks cannot be converted. Husks however will convert into zombies if underwater, and then convert into a drowned some time later like a normal zombie does.

Data values
Zombies have entity data associated with them that contain various properties of the mob. Their entity ID is.

Trivia

 * The rarest mob $1/3$ is a baby zombie riding a brown panda, which has a 2.88×10−13 chance (one in 3.47 2 trillion) of spawning.