Wither Skeleton

Wither Skeletons are dangerous hostile mobs that spawn in Nether fortresses.

Spawning
Wither skeletons will only spawn near nether fortresses at a light level of 7 or less. Skeleton spawn eggs are able to spawn wither skeletons instead of regular skeletons 80% of the time in the Nether. Similarly, when a spider is spawned in the Nether (by the player, monster spawner, etc.), it has a 0.8% chance of spawning with a wither skeleton or a Wither Jockey. Wither skeletons, like all other undead mobs (except withers), will sometimes wear pumpkins on Halloween.

Wither Skeletons are now just over 2.5 blocks high as of 1.8, and require 3 vertical blocks of space to spawn.

Drops
Wither skeletons drop 0-1 coal, 0-2 bones. They have a 2.5% chance of dropping their skull when killed by the player or tamed wolf. They may rarely drop the stone sword. If the wither skeleton is killed by a charged creeper's explosion, they will drop a wither skeleton skull.

Behavior
When the player is attacked by a wither skeleton, they are inflicted with the I effect for 10 seconds, which turns the health bar black and decreases the health gradually. Wither skeletons attack with a stone sword, dealing on easy,  on normal and  on hard. If a wither skeleton is wielding a bow, it will use it like an ordinary skeleton, but the arrows it shoots will always be set on fire, regardless of enchantments. Wither skeletons can sprint.

Trivia

 * Wither skeletons can be afflicted with the Wither effect.
 * Wither skeleton skulls appear on the Xbox 360 Version, although Wither skeletons themselves do not.
 * Wither Skeletons have the same ID as normal skeletons, and therefore attempt to hide under trees in daytime in the overworld, regardless of the fact they cannot burn. They also set on fire in the daytime but immediately get put out, like zombie pigmen.

Gallery
Witherskelett Esqueleto Wither Wither squelette Scheletro Wither Witherskelet Mroczny szkielet Скелет-иссушитель 凋灵骷髅