Witch

Witches are hostile, ranged mobs commonly spawning in Witch Huts. They're the second hostile ranged mob to spawn in the Overworld - the first being the skeleton.

Appearance
Witches have a similar appearance to the villager mob, and they wear purple and green robes with brown leggings underneath. They have large noses (which moves slowly around on the Witch's face, as stated in Dinnerbone's tweet) with a single wart and have lavender colored eyes. Unlike a villager, a witch does not have a mouth. They wear the usual witch hat with a green buckle on it, and their skin is slightly paler than the normal villager. However, witches periodically give off purple star particles similar to the villager's green stars.

Uses
When killed, witches can drop a great number of items, including Glass Bottles, Glowstone Dust, Gunpowder, Redstone Dust, Spider Eyes, Sticks, and Sugar. They drop 1–3 item types, each 0–2 times. The same type can be chosen multiple times, therefore it is possible to get up to six of a one item, or up to two of 3 different items.

Witches also rarely drop Potions of Healing, Fire Resistance and Swiftness, but only when they are killed while drinking that potion.

Combat
The witch mob uses splash potions of poison, weakness, damage, and slowness to fight the player. The current order of potions thrown is; slowness, poison, they will then proceed to throw potions of harming until the player is no longer poisoned which they will rectify by throwing another splash potion of poison and will continue to do this. The splash potion of harming will occasionally be substituted by potions of slowness. These potions will affect other mobs - not just the player. The witch does not burn in sunlight and when set on fire, drinks a potion of fire resistance. This can be seen when a bottle appears in the witch's hands. Utility mobs will attack witches as most other hostile mobs.

Witches are almost immune (85% damage resistance) to splash potions of poison and instant damage. When damaged, they will drink a potion of healing, healing themselves. When drinking a potion, a witch's nose will point straight forward (instead of down). While healing they can't attack the player. If lit on fire by lava or fire, witches will quickly drink potions of fire resistance, making lava and fire ineffective ways of killing witches.

A bow will likely be the best weapon for dealing with a witch, as the splash potions have only a short range (at most nine blocks) compared to arrows (which, when fired straight at full charge, travel 24 blocks). If a bow is not an option, a direct melee charge is the best option. Due to the witch's slow attack speed, if the player runs in a straight line and manages to get a quick sword strike in, the witch will try to heal themselves with a potion of healing, leaving the player to attack them without fear of retaliation.

Farming
it is also possible to make a witch farm, which is useful to create a renewable source of redstone dust, glowstone dust and glass bottles.Ever since snapshot 12w38a,the witch is the most useful for collecting gunpowder,dropping up to 6 instead of 2 from Ghasts and Creepers.

Bugs

 * When a witch drinks a potion, the bottle will not show the drinking animation; only the witch itself.
 * Frequently, they will not spawn in the Witch Hut. However, sometimes they may spawn later after their hut generates.
 * Witch Huts are 2 blocks tall inside and witches are 3 blocks tall so their hats glitch through the ceiling.
 * In Superflat worlds witches don't spawn in witch huts after the world generates.

Trivia

 * If a witch shoots another witch with a potion, the witch who is hit will become angry, however it is impossible for either witch to kill the other (without help from a player) due to their power to regenerate health.
 * Though it's not actually a villager, the witch's skin is found in the Villager folder in minecraft.jar.
 * Witches have more mob drops than any other mob in the game.
 * Witches have the most health of any normally aggressive mob other than boss mobs. However, maximum-sized Magma Cubes may take more hits to kill due to their high armor value, and may also spawn numerous smaller versions whose collective health combined with that of their full-sized progenitor is well over that of one witch.
 * Witches are the only non-boss mob to naturally regenerate health.
 * Unlike villagers, witches do despawn when the player is out of range since they are hostile mobs.
 * Witch Huts are similar to the hut of Baba Yaga (a famous witch in Slavic folklore) that stood on chicken legs.
 * The odds of a witch dropping the maximum amount of drops possible (6 items total) without a Looting enchantment are 81 to 1 (1.2%).
 * Witches are extremely difficult, though not impossible, to be killed by suffocation or drowning, due to their frequent use of healing potions.
 * If another naturally generating structure, such as a desert or jungle temple, spawns in close proximity with a swamp biome, there's a chance that multiple witches may also spawn inside them.
 * Once two witches attack each other they normally can’t stop because of their unique ability to heal themselves combined with the identical attacking patterns of individual witches.