Java Edition guides/The Update that Changed the World

This guide is a simplified overview of all the changes in The Update that Changed the World ( 1.7.x releases), which assumes at least some familiarity with the Horse Update (Java Edition 1.6.x releases).
== Mobs ==
=== New ===
Chicken Jockey		
* Chicken Jockey and Zombie Villager Jockey spawn in Overworld, Zombie Pigman Jockey spawns in the Nether	
Chickens drop:
* 0–2 
* 1 , when not killed by fire
* 1 , when killed while on fire
* if killed by a player or tamed wolf.
Baby zombies drop:
* 0–2 , and rarely s, es and s.
*, plus per equipment piece (when killed by a player or tamed wolf)
* Baby zombies also have a 8.5% chance each of dropping their 
** 
** 
** or any equipped armor that they spawned with. The chance of each can be increased by 1% per level of Looting, up to 11.5% chance. The equipment is usually badly damaged, and may be enchanted.
If killed by a charged creeper, it drops a .	
=== Changed ===
Iron Golems 		
*Drop poppies instead of roses.
Creepers 		
*Can be detonated using a flint and steel.
Zombies 		
*Reduced the lag that zombies created by pathfinding. 
*Can now spawn with and drop armor, bows and swords with the "Unbreaking" enchantment.
Witches 		
*Now drink a potion of water breathing, when they are trapped underwater.
*Can drop a potion of water breathing upon death, as a rare drop.
*Have been added to the mix of low light-level hostile mobs, spawning anywhere where the light level is below 7, including at night in every biome and in caverns.
*They have roughly the same spawn rate as endermen, and much like them they usually appear in groups of 2.
Spiders, Cave Spiders & Endermen		
*Don't become hostile when attacking them in creative mode.
== Blocks ==
=== New ===
Stained Glass 		 	
Any (only drops itself with Silk Touch.) 	
*Can be crafted into stained glass panes using the same recipe as normal glass panes.
*Can be used as decorative block.
Stained Glass Panes 		 	Any (only drops itself with Silk Touch.) 	
*Can be used as decorative block.
Packed Ice 		Generates in Ice Spikes biomes. 	Pickaxe (only drops itself with Silk Touch) 	
*Unlike normal ice, does not turn into water when broken, and does not melt when exposed to heat, and is an opaque solid block.
Red Sand 		Generates in Mesa biomes. 	Shovel 	
*Can be smelted into glass and crafted into TNT.
Podzol 		Generates in Mega Taiga biomes. 	Shovel (drops Dirt unless collected with Silk Touch)	
*Can have plants placed on it, and can be turned into farmland by a hoe.
Acacia and Dark Oak Logs 		Found naturally as part of their corresponding tree types, which generate in Savanna and Roofed Forest biomes, respectively.	Axe 	
*Can be crafted into planks of the corresponding wood type.
Acacia and Dark Oak Wood Planks 		 	Axe 	
*Can be crafted into Stairs and Slabs.
Acacia and Dark Oak Stairs and Slabs 		 	Axe 	
*Can be used as building blocks.
Acacia and Dark Oak Leaves 		Found naturally on their respective tree types. 	Shears 	
*Have a chance to drop their respective sapling types.
*Dark Oak Leaves also have a chance to drop an apple.
*Both have the same texture as Oak Leaves during this version.
Acacia and Dark Oak Saplings 		Drop from their respective leaf types. 	Any 	
*Can be placed in flower pots.
*Grows into their respective tree type if planted on dirt, given adequate space. (Dark Oak Saplings require a 2x2 square of saplings into order to grow into one tree.)
Poppy 		Generates in any biome. 	Any 	
*Can be crafted into red dye.
*Can be placed in flower pots.
*Replaces the Rose.
Azure Bluet 		Generates in Plains and Flower Forests. 	Any 	
*Can be crafted into light gray dye.
*Can be placed in flower pots.
Oxeye Daisy 		Generates in Plains and Flower Forests. 	Any 	
*Can be crafted into light gray dye.
*Can be placed in flower pots.
Blue Orchid 		Generates in Swamps. 	Any 	
*Can be crafted into light blue dye.
*Can be placed in flower pots.
Allium 		Generates in Flower Forests. 	Any 	
*Can be crafted into magenta dye.
*Can be placed in flower pots.
Tulips 		Red, orange, white and pink tulips can be found in Plains and Flower Forest biomes. 	Any 	
*Can be crafted into red, orange, light gray and pink dyes.
*Can be placed in flower pots.
Rose Bush 		Generates in Forests, Birch Forests, Flower Forests and Roofed Forests. 	Any 	
*Can be crafted into red dye.
*Drops a duplicate of itself when right-clicked on by bone meal.
Peony 		Generates in Forests, Birch Forests, Flower Forests and Roofed Forests. 	Any 	
*Can be crafted into magenta dye.
*Drops a duplicate of itself when right-clicked on by bone meal.
Lilac 		Generates in Forests, Birch Forests, Flower Forests and Roofed Forests. 	Any 	
*Can be crafted into pink dye.
*Drops a duplicate of itself when right-clicked on by bone meal.
Sunflower 		Generates in Sunflower Plains. 	Any 	
*Can be crafted into yellow dye.
*Drops a duplicate of itself when right-clicked on by bone meal.
*Always faces east (toward positive X).
Double Tallgrass 		Generates in numerous biomes, and can be created by applying bone meal to tall grass. 	Shears 	
*Can be used decoratively.
*Have a chance of dropping Wheat Seeds when broken without Shears.
Large Fern 		Generates in numerous biomes, and can be created by applying bone meal to ferns. 	Shears 	
*Can be used decoratively.
Infested variants of Mossy Stone Bricks, Cracked Stone Bricks and Chiseled Stone Bricks		Generate in strongholds, and form when silverfish infest the respective normal block type. 	Pickaxe (drops nothing) 	
*Spawn Silverfish when broken.
Grassless Dirt 		Generates naturally in certain Savanna biome variants and is obtainable only through commands. 	Shovel (drops normal dirt) 	
*Has the same appearance as normal dirt, but grass and mycelium cannot grow on it.
=== Changed ===
Wood 		
*Wooden logs have different textures for their top and bottom
**Oak Wood remains the same, as if being the default.
Cauldrons 		
*Cauldrons with water in them extinguish burning entities, taking away one water level each time.
Sugar canes 		
*Color/shade is affected by the biome color (similar to leaves, grass and vines).
Dead bushes 		
*Can be placed on hardened clay, stained clay, red sand and dirt.
Command blocks 		
*Show what command it ran recently in the GUI.
*Extended character limit past the 10,000 mark.
Iron bars & glass panes		
*Connect to each other and glass blocks.
**This includes panes of different colors.
== Items ==
=== New ===
Pufferfish 		Can be obtained from fishing.	
*Can be used for restoring hunger 
** Restores hunger.
**If eaten, it inflicts
***Poison IV (1:00)
***Hunger III (0:15)
***Nausea (0:15)
*Used to brew a water breathing potion.
Clownfish 		Can be obtained from fishing.	
*Can be eaten to restore hunger.
Raw Salmon 		Can be obtained from fishing.	
*Restores hunger.
*Can be cooked into Cooked Salmon.
Cooked Salmon		 	
*Restores hunger.
== Potions ==
=== New ===
		
* Water Breathing
== Non-mob entities ==
=== New ===
Minecart with Command Block		Can be obtained only through commands.		
*Functions much like a command block, but is mobile, and can be activated by activator rails.
== Enchantments ==
=== New ===
Enchantment 	Max Level	Applicable Items	Notes
Lure 	III 	 	
*Decreases the wait time for catching something.
Luck of the Sea	III 	 	
*Increases luck while fishing.
== Structures ==
=== New ===
Acacia Tree 		Generate in Savanna biomes and when grown from Acacia saplings. 	No	None	
*The most common trees in Savannas, and a source of Acacia wood.
Dark Oak Tree 		Generate in Roofed Forest biomes and when grown from a square of 4 Dark Oak saplings.	No	None	
*The most common trees in Roofed Forests, and a source of Dark Oak wood.
Mega Spruce Tree		Generate in Mega Taiga biomes and when grown from a square of 4 Spruce saplings. 	No	None	
*The most common trees in Mega Taigas, and a source of Spruce wood.
Forest Rock 		Generate in Mega Taiga biomes. 	No	None	
*Found throughout the surface of Mega Taigas, and a source of Mossy Cobblestone.
Ice Spike 		Generate in Ice Spike biomes. 	No	None	
*The most striking feature of Ice Spike biomes, and a source of Packed Ice blocks.
== Biomes ==
=== New ===
Mesa 		
* Contains mountains composed of multiple types of colored hardened clay that are layered in a way that resembles sedimentary rock.
** There are seven colors including normal, orange, red, yellow, white, light gray and brown.
* The flat lands below the mountains are similar to a desert biome, but made of red sand instead of sand.
* Dead bushes and cacti spawn in this biome.
* Occasional dying forests spawn on top of the clay mountains.	
*Oak trees (in some variants)
Savanna 		
* A flat and dry biome with a sparse covering of acacia trees, with plateaus and the occasional giant mountain.
* Inhabited by horses, and villagers in villages identical to those in plains.	
*Villages
*Acacia trees
*Oak trees
Jungle Edge 		
* A jungle variant with much sparser vegetation and only small jungle trees.	
* Jungle trees
Sunflower Plains 		
* Exactly the same as plains, but contains a large amount of sunflowers.	
*Villages
Flower Forest 		
* Forest variant containing a dense ground covering of a wide variety of flowers.
* Contains the exclusive Allium flower, along with every other flower type, except Blue Orchids and Sunflowers.	
*Oak trees
*Birch trees
Roofed Forest 		
* A dense forest of Dark Oak Trees containing oak and birch trees and giant mushrooms.
* The canopies of the trees form a mostly unbroken "roof" that blocks out sunlight.
* Monsters are often able to spawn during the day due to the darkness.	
*Giant mushrooms 
*Dark Oak trees
*Oak trees
*Birch trees
Birch Forest 		
* A forest made entirely of birch trees.
* Has a variant with taller birch trees that cannot be grown from saplings.	
*Birch trees
Taiga 		
* A forest of spruce trees with bluish grass.
** The previous snowy version of the Taiga biome is now called the "Snowy Taiga" instead.
* Contains a large amount of ferns.	
*Spruce trees
Mega Taiga 		
* A forest of giant 2x2 spruce trees, which tower above the regular spruce trees that grow between them.
* Much of the ground is covered in podzol.
* Mossy cobblestone "boulders" are scattered around in this biome.
* Dead bushes, mushrooms and ferns cover the forest floor.	
*Spruce trees
*Mossy cobblestone boulders
Gravelly Mountains 		
* An extreme hills variant with a surface largely composed of gravel.	
*Oak trees
*Spruce trees
Wooded Mountains 		
* An extreme hills variant with a much denser covering of trees.	
*Oak trees
*Spruce trees
Stone Shore 		
* A beach biome with terrain made of stone, which often generates between extreme hills and oceans.	
Ice Spikes 		
* A snowy biome covered in large pillars of packed ice blocks.
* The surface is made out of snow blocks on top of dirt.	
*Ice spikes
Deep Ocean 		
* Is about ten blocks deeper than normal oceans; the maximum depth is in the low 30s.
* Has a seafloor made entirely of gravel.	
Biome Variants/Technical Biomes		
* Over 20 variants for new and existing biomes.
** M – Biomes with an M variant are rarer than the normal version of that biome and contain some specific modification, such as taller trees or more water pools.
** Plateau – Biomes with a plateau variant are like the hills technical biome, but flattened at the top.
** Mesa (Bryce) – A rare variant of the mesa biome that works similar to ice spikes, with tall clay spikes generating from the sandy mesa floor.
** Hills – More technical hills biomes have been added to fit with the new biomes.
** Stone Beach – Generates between mountains and oceans to create rocky cliffs.	
=== Changed ===
* Each biome now has a "temperature" value. Biomes with similar temperature values are more likely to generate next to each other.
* Biomes can be divided roughly into 4 categories based on how their temperature affects precipitation:
**In hot biomes, it never rains.
**In warm biomes, it rains at all altitudes.
**In cool biomes, it rains at low altitudes and snows at high altitudes.
**In snowy biomes, it snows at all altitudes.
* Many existing biomes have been updated, and some have received slightly different variants where some key aspect of the generation is different:
Desert 		
*Added Desert Lakes, a Desert variant containing water lakes.
**Similar to pre-1.6 Deserts.	
*Desert Wells
*Desert Temples
*Villages
Jungle 		
*New variants include Modified Jungle, Jungle Edge, and Modified Jungle Edge.
*Melons now generate in Jungles.	
*Jungle Temples
*Jungle trees
*Oak trees
Swamp 		
*Added hilly variant.
*Changed grass color.
*Added Blue Orchids.	
*Witch Huts
*Oak trees
Forest 		
*Contain multiple new flowers.	
*Oak trees
*Birch trees
Plains 		
*Contain multiple new flowers.	
*Villages
Extreme Hills		
*New terrain generation for Extreme Hills
*Extreme Hills now have large amounts of exposed stone and gravel on their surface.
*Now contain spruce trees.
*New variants include Wooded Mountains and Gravel Mountains.
*Stone Cliffs now generate between Mountains and Oceans.	
*Oak trees
*Spruce trees
Snowy Taiga 		
*Renamed from "Taiga" to "Snowy Taiga".
*Added mountainous variant.	
*Spruce trees
== World types ==
=== New ===
Amplified		
* It scales up all world generation rules, so it uses the entire world height.
** Almost all biomes can generate huge mountains that can reach well above Y: 200.
*** Extreme Hills biomes frequently reach the world height limit at Y: 256.
*** Swampland and ocean biomes are unaffected by this world type.
* Extremely resource intensive and requires powerful computer to run.
* Ravines here can reach down to bedrock.
* Contains numerous various landforms that are very rare or non-existent in default generation.
** Some examples include floating islands, overhangs, large water and lava falls and huge indents.
* Taiga biomes reach such altitudes that snow starts generating (about Y=130).	All structures
== Music tracks ==
Note: these track previews have been shortened to 30 seconds on the wiki due to an agreement with the author to allow them on the wiki
=== New ===
creative1.ogg	Creative mode 	"Biome Fest" 	
creative2.ogg	Creative mode 	"Blind Spots" 	
creative3.ogg	Creative mode 	"Haunt Muskie" 	
creative4.ogg	Creative mode 	"Aria Math" 	
creative5.ogg	Creative mode 	"Dreiton" 	
creative6.ogg	Creative mode 	"Taswell" 	
nether1.ogg 	The Nether 	"Concrete Halls" 	
nether2.ogg 	The Nether 	"Dead Voxel" 	
nether3.ogg 	The Nether 	"Warmth" 	
nether4.ogg 	The Nether 	"Ballad of the Cats"	
boss.ogg 	Ender Dragon battle	"Boss" 	
end.ogg 	The End 	"The End" 	
menu1.ogg 	Main menu 	"Mutation" 	
menu2.ogg 	Main menu 	"Moog City 2" 	
menu3.ogg 	Main menu 	"Beginning 2" 	
menu4.ogg 	Main menu 	"Floating Trees" 	
credits.ogg 	End Poem 	"Alpha" 	
== Achievements ==
=== New ===
ja:ガイド/Java Edition/世界を変えたアップデート
zh:Java版指南/改变世界的更新
ru:Руководства по Java Edition/The Update that Changed the World