Skeleton

Skeletons are undead, ranged hostile mobs equipped with bows.

Strays are variants of skeletons that only appear in snowy biomes.

Spawning
Skeletons can spawn almost anywhere in the Overworld at a light level of 7 or less. In the Nether, they can also spawn in nether fortresses at a light level of 7 or less in place of a wither skeleton.

Spiders have a 1% chance to spawn with a skeleton riding them, creating a spider jockey.

Skeleton riders spawn when a skeleton trap is triggered by a player. The skeletons ride on skeleton horses and are equipped with enchanted bows and iron helmets, and have damage immunity for 3 seconds after spawning.

Skeletons are 1.99 blocks tall.

Monster spawners
Skeletons also spawn from spawners found in dungeons.

Drops
Skeletons drop:
 * 0–2 s
 * 0–2 s
 * 0-1 (strays only)
 * Any picked-up equipment has a 100% chance of dropping and will drop with the same damage level it had when picked up.
 * Any naturally spawned equipment (including the bow) has a 8.5% (9.5% with Looting I, 10.5% with Looting II and 11.5% with Looting III) chance of dropping. It will usually be badly damaged, and has a chance of being enchanted.
 * A skeleton will drop its head if killed by a charged creeper's explosion.
 * Skeletons drop 5 experience when killed by a player or tamed wolf, +1–3 extra experience if the skeleton has equipment.

Wither Skeleton
Wither Skeletons are a variant of skeleton, but taller, darker and more dangerous than regular skeletons. They have a sword instead of a bow, and spawn in nether fortresses, and also in the general nether. They inflict the Wither status effect while attacked by one. See here for more information of the mob.

Stray
"Stay alert as you travel through the frozen landscape: there are more deadly things here than the cold! Lurking in the snow are strays - ragged wanderers with baleful eyes and deadly bows, ever on the lookout for foolish warm-bloods intruding into their territory. And beware! Those arrowheads will do more than stick you - their icy tips will cast a freezing pall, slowing their hapless victim to a frosty shuffle."

- Marsh Davies

80% of skeletons spawned directly under the sky in ice plains, ice mountains, and ice plains spikes biomes will be strays. Strays will not spawn from naturally spawned monster spawners, even when exposed to direct sky. The 1% of spiders spawned in those biomes which end up spawning as a spider jockey also have an 80% chance to be a stray spider jockey. The stray has its own spawn egg in Creative mode.

Strays behave much the same as normal skeletons do. However, they shoot tipped arrows that inflict for 30 seconds on any target that it hits. Despite shooting Slowness arrows, strays themselves are not immune to Slowness.

Strays make similar noises to skeletons, but with the addition of an echoing effect.

In addition to normal skeleton drops, strays have a 50% chance to drop a arrow of Slowness. With the Looting enchantment, this chance increases to $2×level+1/2×level+2$, which comes to $3/4$ for level I, $5/6$ for level II, and $7/8$ for level III.

Halloween
During Halloween, skeletons have a 22.5% chance of spawning wearing a pumpkin and a 2.5% chance of spawning wearing a jack o'lantern. If these skeletons are killed using a tool 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.

Behavior


Skeletons spawn in dimly lit areas (light level 7 or lower), and will burn in sunlight. Skeletons will chase any player they see within 16 blocks, and will climb stairs, navigate mazes, and traverse other complex obstacles in order to get within shooting range. When they are within about 8 blocks of the player with a clear line of sight, they will stop chasing and start shooting the player with arrows, one arrow on each 2 seconds (1 in hard difficulty). They will strafe at player's walking speed in circle patterns to try to dodge attacks during the process, and will retreat to safe range if the player comes too close (4 blocks or less) to them. If the player moves more than 16 blocks away from the skeleton, it will cease pursuit. The detection range of skeletons is reduced to half of their normal range (8 blocks) when the player is wearing a skeleton mob head. If a player shoots a skeleton outside its detection range, then it will temporarily hold up its bow in a shooting position.

The skeleton's accuracy is based on the difficulty. Skeletons have an "error" of 10 on easy, 6 on normal, and 2 on hard. This is compared to the player's "error" of 1. When their target is closer, skeletons shoot faster, but do less damage. To account for gravity, skeletons aim 0.2 blocks higher for every block horizontal they are from the target.

If a skeleton's arrow hits certain hostile mobs, that mob will then attack the skeleton the same way it would attack the player, given it was not hit by the player first. If a skeleton is attacked by another mob (usually another skeleton), it may attack that mob, reorienting on the player once that mob is dead.

If spawned with no weapon at all (by using commands) a skeleton acts like a zombie (though faster), coming at the player with arms outstretched and damaging the player by touching them.

Skeletons are also able to climb ladders, but only when forced to, as their AI does not handle ladders in a special way.

Like zombies, skeleton burning occurs at dawn when the sun is 15 degrees or greater above the ground, unless the skeleton is either in shade, water, or wearing a helmet. If not wearing a helmet, they will attempt to find shade or water to keep from burning. Unlike zombies, which will always chase the player if they see one, skeletons will not exit the shade area even if attacking a player. Burning skeletons have a 50% chance of shooting flaming arrows if the raw regional difficulty is 3 or greater.

Skeletons holding tipped arrows in their offhand will shoot that type of arrow; these arrows are not consumed.

Skeletons run from wolves, as wolves attack and chase skeletons. When skeletons are safe from sunlight, they will shoot at any wolves that attack it. Skeletons will also shoot at iron golems. Creepers killed by a skeleton's arrow will drop a music disc.

Skeletons are undead mobs, and are damaged by the status effect Healing, healed by the status effect Harming and unaffected by the status effects Regenation and Poison

Armed and armored skeletons


Like zombies, some spawned skeletons can pick up dropped items from the ground, and if those items happen to be armor, pumpkins, jack o'lanterns or mob heads they will equip them, and if weapons or tools, the skeleton will use them as a melee weapon.

Skeletons spawn already-armed with bows, which may also be enchanted. The chances of that event are listed below and are taken from the game's code. If a skeleton 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 skeleton does spawn with armor, the chances of specific armor are as follows:

The chances of it being of a particular material are:

Skeleton armor is not damaged from most damage sources, which means it cannot "wear out" the way player armor does. Helmets (not blocks like pumpkins) on skeletons can wear away and break if the skeleton is exposed to daylight or has an anvil or other falling block dropped on its head.

If a skeleton has a bow and a sword is given, it will drop the bow (with the same chance as if killed with Looting I) and start using the sword. If a skeleton has a sword or bow in their hand, and one of a better type or with better enchantments is given, they will drop the existing weapon (with the same chance as if killed with Looting I) and start using the better one. Any skeleton that spawns with equipment (picked-up items don't count) will give 1–3 extra experience points per item.

Data values
Skeletons and strays have entity data associated with them that contain various properties of the mob. Their entity IDs are  and   respectively.


 * Skeleton


 * Stray

Trivia

 * If alerted to a player's presence, skeletons can fire arrows backwards, occasionally hitting themselves.
 * Skeletons cannot see the player through glass, fences, or other transparent blocks.
 * According to Jeb, the concept for the stray emerged from a game jam the Bellevue team had, where they were just adding a bunch of stuff to Minecraft - whatever they wanted. Jason Major made a bunch of cool mobs and he thought this one fit really well with what they were already planning.