Wither

The wither is a powerful, floating undead boss mob that shoots explosive skulls at its enemies, and is currently the only player-made hostile mob in the game.

Spawning
The wither is spawned by placing 4 blocks of soul sand in a T shape, and putting 3 wither skeleton skulls on top of the three upper blocks. The last block placed must be one of the three skulls, and can be placed by the player or a dispenser. Air blocks are required on either side of the base soul sand block under the upper blocks (keep in mind that "block" refers to any block, not just those that are block shaped; therefore objects such as Grass and flowers still prevent the Wither from spawning). The building pattern can have any orientation (including horizontal) as well as the skulls. When the wither has completely spawned, it becomes angered and creates an explosion around itself.

Like other hostile mobs, the wither despawns when the difficulty is changed to Peaceful. The wither spawning structure also fails in peaceful difficulty; the blocks simply do nothing.

Drops
The wither drops the nether star upon death which, until picked up, cannot despawn or be destroyed by explosions. The Looting enchantment does not increase this drop. It also drops 50 experience points when killed by a player or tamed wolf.

Behavior
When spawned, the wither grows larger in size as its health bar fills up. While in this state, the wither is invulnerable, and neither moves nor attacks. When this state ends (after 10 seconds), the wither creates a very large explosion centered on itself, destroying nearby blocks and dealing up to 68 × 34 damage to nearby mobs/players. This “birth” explosion is larger than that of a charged creeper or an end crystal and is accompanied by a loud, threatening, ghastly sound that can be heard equally from across the map, and isn’t actually centered on the wither. After this, the wither attacks nearby mobs and can take damage.

The wither is immune to fire, lava and drowning damage. Suffocation is ineffective, since upon taking damage, the wither breaks any block it touches (except bedrock, end gateway blocks]‌, end portal blocks, end portal frames, command blocks, barriers and extended pistons). Like other Undead mobs, the wither is harmed by the Instant Health effect and healed by the Instant Damage effect. It is immune to all other status effects, like the ender dragon. However, it takes extra damage from weapons with the Smite enchantment.

The wither is hostile towards all mobs except the following: Hostile mobs that can be targeted by the wither include spiders and guardians.
 * Zombies and their variants
 * Skeletons and their variants
 * Zombie pigmen
 * Undead horses
 * Phantoms
 * Players in creative or spectator mode
 * Ghasts
 * Other withers

The wither is immune to all attacks from other undead mobs except skulls from other withers.

If the wither is idle, it simply hovers and is unable to gain altitude. On Normal or Hard difficulty, it also randomly fires blue skulls in random directions until it finds a target.

The wither has a dark purple boss health bar that appears only when a player is looking in the wither's direction, including through walls. When looking at the wither, the sky gets slightly darker. All withers display a boss bar on the screen.

Upon noticing a player or mob, the wither flies to a random location and hovers in place. It shoots 3 black wither skulls and a blue wither skull before flying to another location.

At half health, it causes a large explosion that spawns 3-4 wither skeletons (except on Easy difficulty), as well as gaining "wither armor". Instead of flying to a random location, it dashes towards its target, destroying most blocks and damaging mobs in its path. It also fires up to 4 skulls per burst. It has different birth and death animations, both of which involve the wither spinning and exploding.

Wither Skull
The wither shoots explosive projectiles called wither skulls, which look like extra heads of itself, at its target. There are two types of wither skulls: a fast-moving black one, and a slower blue one. Black wither skulls explode with a blast radius of 1, the same as a ghast's fireball, and cannot break blocks with a blast resistance above 20. The blue wither skull has the same explosion strength, but moves slower and treats most blocks as having a blast resistance of no more than 4, making it more destructive to the terrain.

If either type of wither skull hits a player or mob, it inflicts the wither effect, which turns the health bar black and drains health, similarly to poison.

Like other harmful status effects, the wither effect can be cured by drinking milk] or using a [[Totem of Undying|totem of undying.

The blue skull can be deflected by hitting it with hand or throwable entities (similar to ghast fireballs).

Entity data
Wither skulls are also entities that have associated entity data.
 * Entity data
 * Tags common to all entities [show]
 * direction: List of 3 doubles. Should be identical to Motion.
 * life: Increments each tick when the projectile is not moving; resets to 0 if it moves. Has no effect, though is still saved/read
 * power: List of 3 doubles that adds to direction every tick. Act as the acceleration.

Data values
Withers have entity data associated with them that contain various properties of the mob.
 * Entity data
 * Tags common to all entities [show]
 * Tags common to all mobs [show]
 * Invul: The number of ticks of invulnerability left after being initially created. 0 once invulnerability has expired.

Achievements
Main article: Achievements

Trivia

 * According to Jeb, the wither was inspired by Terraria, which has a summonable boss mechanic. The name itself is inspired by poison spell in another game made by Jeb called Whispers in Akarra.
 * There is a painting showing the soul sand and [Mob Head|wither skeleton skull]] formation needed to spawn a wither.
 * The wither does not take damage from undead mobs' attacks.
 * If the wither is damaged by the Void, it frantically attempts to fire blue skulls.
 * Above half health, the Wither always attempts to stay a few blocks above the mob it is targeting. This means that attempting to build or climb up to hit the Wither using a sword is essentially impossible.
 * If the wither is after a blaze and the blaze tries to fly up to it, the wither attempts to keep rising above the blaze, thus making both of them rise higher until they hit a ceiling or until the blaze despawns.
 * Although the wither is 3.5 blocks tall, 3 blocks wide, and 1 block thick, its hitbox is only 3.5 blocks tall, 1 block wide, and 1 block thick.
 * The true dimensions of the wither are: 2.844 blocks tall (varies), 3 blocks wide and 1.719 blocks long (also varies).
 * Summoning the Wither in a small underground room at the end of a long tunnel can make the fight easier, as the Wither does not have as much space to maneuver. Back up along the tunnel and the Wither needs to destroy blocks continuously to chase after you, hopefully allowing you time to shoot arrows to whittle down its health.
 * The wither spawn structure can be built any way, such as downward or horizontal, however the wither always spawns at the foot of the structure.
 * The wither appears on four sides of chiseled red sandstone.
 * Withers have the greatest natural health of all vanilla mobs in Minecraft, making it brawnier than even the ender dragon. The wither, however, is slower and deals less damage than the ender dragon.
 * The wither's smaller heads shoot targets slightly slower than the main head. the interval for smaller heads is 2-3 seconds, while the main head's always 2.
 * An enemy called the Wither Storm appears in Minecraft: Story Mode. It was created by replacing the center block of soul sand with a Command Block.
 * Despite not having visible feet, withers are still capable of making footstep sounds.

Gallery

 * 

The withering effect after being damaged by a Wither Skull.
 * 

The "wither armor" that blocks arrows.
 * 

A larger image to show how to summon the wither.
 * 

A blue Wither.
 * 

The pit created after the wither has charged.
 * 

The wither attacking horses

In Other Media[edit]

 * 

Wither Storm, a variant of Wither as it appears on Minecraft: Story Mode.