New world generation in Java available for testing

(Bedrock version here)

UPDATE (Sep 8): Snapshot 7 is shipped! This one is tiny so don't get too excited. You might not even notice any difference. But if you do let us know what you think :) 

Also this is probably going to be the last experimental snapshot for now. We are focusing on getting these tweaks into the normal Java snapshot and Bedrock beta series.

With Caves & Cliffs: Part I released, we’re currently hard at work at delivering the second chapter. In Caves & Cliffs: Part II, we’re not only updating the caves and adding new mountains – we are also changing the overall terrain generation to make it all fit together. As these features will bring pretty big changes, we would love your feedback! 

We need to sort out some technical things before we can ship these in a normal Java snapshot or Bedrock beta, so in the meantime, we've created an experimental snapshot for Java that you can download separately. That way, you can try out the all-new world generation and provide us with feedback while we continue our grand work of terraforming the world of Minecraft and integrating it into our normal snapshot/beta series. 

Changes in experimental snapshot 7 compared to snapshot 6

• Noodle caves can generate at any height, no longer capped at y 130. This means you'll sometimes find tiny cave openings and cracks in mountain peaks. Tread with care.
• Some parts of the terrain are ever so slightly smoother (less 3d noise in tech speak)
• Elytra doesn't take durability damage when gliding, only when using rockets. So you don't HAVE to have mending or unbreaking enchantments to use your elytra, especially now that there are higher mountains and cliffs to launch from.
• Elytra rocket boost is a bit weaker, so you can't fly as fast with rockets. We are testing this for several reasons:
  • Elytra rocket boosting is so fast that other means of transport become almost redundant. We want to balance it out a bit.
  • Even in earlier versions of Minecraft most servers get laggy when players fly around with elytra & rockets because they fly faster than chunks can load. With the new world height this would probably get worse.
  • There is so much more cool terrain to enjoy now, wouldn't want to zoom past it all too fast right? :)
  • Note that gliding speed is unchanged. This affects just rocket boosting.
• That's it. I told you. This is a tiny snapshot.
• What? The swamps, you ask? Nope, we didn't change the swamps, and they have mixed feelings about that.

Changes in experimental snapshot 6 compared to snapshot 5

• Tweaked placement of the new mountain biomes so they match the mountain terrain and temperature better. Grove and snowy slopes are less likely to generate on mountain peaks. In cold climates grove and snowy slopes tend to start much lower down, while in temperate and hot climates they tend to start higher up.
• Tweaked biome placement to reduce the risk of cold microbiomes, such as a small splotch of snowy tundra in the middle of a forest (birdpoop microbiomes). It can still happen, but not as often.
• Fixed an accidental change from last snapshot that made lush caves smaller and more fragmented. Now they should be about as common as in snapshot 4 again.
• Giant tree taiga and giant spruce taiga no longer count as cold climates from a biome placement perspective. So these biomes are less likely to mixed in with snowy biomes. This caused a small reshuffle of other biomes to maintain the overall balance.
• Slightly reduced the number of water springs.
• Slightly increased underwater magma, to increase the chance of finding air when diving in aquifers.
• Cavier ocean floors! Aquifers under oceans/rivers are more likely to link to the underground. This means you are more likely to find cave openings on ocean floors that actually lead somewhere instead of being cut off. One consequence of this is that caves at y0-40 below oceans are more likely to be flooded. If you dive into an underground lake you might end up inside one of those flooded caves and pop out at the bottom of an ocean.
• Underwater ravines are back. Cave carvers can now carve through sand and gravel on ocean floors, so underwater ravines and caves will no longer be hidden under a layer of gravel or sand. As opposed to MC 1.17, we no longer use a specific carver for underwater ravines, we just use normal noise caves and carvers but on ocean floors. So the underwater ravines won't look exactly the same as in 1.17, but we get a lot more natural variation. Magma may still generate inside them, as with all flooded caves.
• Horses, Mules, and Donkeys now follow players holding golden carrots, golden apples, and enchanted golden apples. Makes it easier to get your horse across that deep river! Similarly, llamas follow hay bales.
• That's all.
• No wait, one more thing. Almost forgot the swamps. Swamps can now generate in dry areas. They couldn't in last snapshot, which seemed to make sense, but it turned out that sometimes a very small area will be drier than the surrounding area, causing microbiome issues like small spots of desert in the middle of a swamp. Swamps should be less fragmented now, and they appreciate that.

Changes in experimental snapshot 5 compared to snapshot 4

• Peakier peaks! In some areas mountains have jagged peaks, like in the beloved bedrock beta mountains.
• Made mountain areas and peak biomes slightly larger on average.
• Raised the average mountain height, fixing an unintentional change from snapshot 4 that made mountains lower and smoother. But then we had to lower the mountain height again to fit the peakier peaks, so maybe it evens out. We deliberately avoid having peaks or mountains that go above y260 or so, because we want players to have space to build cool stuff on the peaks. So any peaks that try to sneak too high up get mercilessly cut off into a plateau.
• Fossils with diamonds no longer generate above deepslate level.
• Moved swamps slightly more inland, since they were leaking murky swamp water into the ocean. Oceans are happy about this, swamps are a bit grumpy. Also swamp trees can grow in slightly deeper water than before, so swamp lakes should be less barren.
• Cave carvers can carve through red sand and calcite, so those blocks aren't left hanging in the air.
• Tweaked the depth of rivers and the steepness of river banks. They are less likely to be super deep or get choked off in flat areas. Also rivers integrate better with swamps, the river tends to get shallow and merge with the swamp instead of carving through. Swamps like that, feels less disruptive.
• Small lakes features are no longer placed in dry and hot biomes (desert, savanna, badlands). Reduced the number of lake feature placements in other biomes.
• Small hills and overhangs (3d noise in tech speak) generate more often in flat areas, like in snapshot 3. This was accidentally removed in snapshot 4, causing flat areas to be a bit too flat and featureless.
• Reduced the amount of shattered terrain and shattered savanna biome, replacing some of that space with flatter beaches instead.
• Water springs can generate in more types of blocks such as dirt and snow, increasing the likelihood of small mountain streams and waterfalls. Also added springs to lush caves.
• Fixed an indent in the code. Doesn't matter at all so I don't know why I'm mentioning it here.
• Made badlands slightly smaller on average. Just a bit. But don't worry they still tend to be quite big.
• Added (well, re-added) jungle edge biome. If we keep it we'll probably rename it though, because it isn't really an edge biome any more.
• Tweaked mushroom fields biome so it matches the shape of the islands better.
• Dripstone caves biome place stone surface instead of grass surface when leaking out of cave entrances. This should make dripstone cave entrances less grassy.
• Removed the height-based spawning change that was made in snapshot 3. We appreciate the community discussions about this. We decided to undo the change for now and will come back to this when we have more time.

Changes in experimental snapshot 4 compared to snapshot 3

Changes in experimental snapshot 3 compared to snapshot 2

• Tweaked biome placement to reduce the risk of temperature clashes (such as a snowy biome in the middle of a desert). Temperature clashes still happen, but not as often.
• Tweaked biome placement to allow for more noisiness and diversity again, essentially dialing back some of the changes from last snapshot. This means microbiomes are more likely to happen again, but they will usually be of matching temperatures (for example a small forest inside a plains biome).
• Red sand is back! Tweaked badlands so they sometimes show up in flat areas next to plateaus, and made the red sand generate higher up (to account for the generally higher terrain).
• Made peak biomes and meadows less likely to generate in flat low elevation areas.
• Smoothed out the cliffs in shattered terrain a bit, so they don't look like chunk errors.
• Snowy slopes and snowcapped peaks no longer place dirt under the snow. Mountains look less dirty now :)
• Added a new mountain biome: Stony peaks. This is just a variant of lofty/snowcapped peaks that uses stone and gravel instead of snow and ice, and is used to avoid temperature clashes such as a snowcapped peak sticking up from a jungle.
• Added structures to some of the new mountain biomes. Pillager outposts generate in all the new mountain biomes. Villages generate in meadows.
• Tweaked beaches a bit, to make them more inclined to show up on flat coastlines rather than hilly areas. Also reduced the amount of stone shores.
• Coastlines and river banks are less likely to get messed up by aquifers. That is, local water levels are mostly used in terrain that doesn't border a river or ocean. Cave openings and ravines that intersect an ocean or river will mostly use sea level.
• Inland low-elevation areas are less likely to have flooded caves all over the place.
• Aquifers can go deeper and are more likely to connect with cave systems further down. That means if you dive into a deep lake on the surface (or in a mountain), you will sometimes encounter air pockets that lead to a cave system.
• Added more high-frequency variation to aquifers, to reduce the risk of massively huge areas with waterfilled caves everywhere. Underground lakes and flooded regions are more likely to be spread out instead of concentrated in one region.
• Fixed goat spawning (they weren't spawning in the new mountain biomes)
• Swamps are less likely to overlap cold or dry biomes, and they no longer place hanging water. Swamps are even happier now.
• Desert temples spawn on the surface rather than at a fixed y level.
• Eroded badlands no longer create floating pillars on top of the water surface.
• Grass no longer generates under water
• Reduced the risk of incorrect surface placement such as grass patches in deserts.
• Reduced the risk of river biome generating in dry mountain gorges. We don't have support for actual rivers generating above sea level, so if a mountain gorge is above sea level then it will be dry.
• Mob spawning no longer speeds up in low terrain or slows down in high terrain. The new spawning speed is similar to 1.17 spawning at y=64. This change is intended to make spawning more consistent in the updated overworld.
• Fixed an issue where players in multiplayer can face far more or far fewer enemies than intended, particularly when other players are flying. Each player now gets their fair share of mobs.

Changes in experimental snapshot 2 compared to snapshot 1

• Biome placement is a bit smoother and less noisy. Fewer microbiomes dotting the terrain. Biomes tend to be a bit larger and less fragmented.
• Raised cloud level from 128 to 192
• Renamed mountains (= old mountains biome) to extreme hills, and gravelly mountains to gravelly hills, to reduce risk of people getting confused when they use /locatebiome to find the new mountains and end up in the old mountains...
• Beachier beaches! Beaches are generally wider. But also in some places there are no beaches at all, to provide some variation.
• Sheep spawn in meadows. Also more rabbits and less donkeys
• Blue orchid no longer spawns in meadows. The swamps were sad because this was their unique thing.
• Swamps now generate properly. They generated in weird places before and were sad about that. Swamps are happier now.
• Added missing biomes: Ice Spikes and Eroded Badlands
• Underground biomes interfere less with surface biomes. They can still leak out of cave entrances sometimes though (because it looks kinda cool!)
• Increased the height of some of the peaks. Now they can reach up to 220-260 or so, but rarely.
• Slightly increased the chance of finding large areas with flat terrain
• Meadows sometimes spawn a lone tree, often with a bee nest
• Monsters spawn in the new mountain biomes
• Emeralds and infested stone generate in the new mountain biomes
• Made ore veins slightly larger and more frequent, since very few people seemed to actually find them in survival.
• Structures now show up in the right biomes (mostly). Found the right amount of duct tape to put in the right place in the code.
• Toned down the megacave entrances a little bit, and made them less likely to go all the way down to deepslate level. Getting to diamond zone was just a bit too easy.
• Made cheese caves a little bit smaller on average (they can still be huge though!), and a bit less likely to intersect the surface
• Reduced the chance of sand and gravel being placed in such a way that they immediately fall down on generation. Replaced with sandstone or stone in those cases. The falling blocks were messing up the terrain as well as performance. Still happens but not as often.
• Zombie, Skeleton, Spider, and Cave-Spider spawners now spawn mobs up to block-light level 11. Although the mobs spawning in complete darkness did not affect the difficulty of vanilla spawners, we recognized that these spawners haven't been a real challenge for a while now. We hope this change will make conquering a spawner a more exciting challenge! 
• Spawners have a new "CustomSpawnRules" tag, which lets you override the spawn rules of the spawned mob. In the tag you can specify "BlockLightLimit" which indicates the highest block-light the spawners will spawn mobs at. This change is to enable map-makers to use spawners in a more customizable manner to spawn mobs in any light levels they choose!

Changes compared to Caves & Cliffs: Part I

• New world height and depth

• New mountain biomes (lofty peaks, snowcapped peaks, grove, meadow, and snowy slopes)

• New cave generation (cheese, spaghetti, and noodle caves)

• Local water levels and lava levels in the underground

• New cave biomes generate naturally underground and inside mountains (lush caves, dripstone caves)

• Natural variation in terrain shape and elevation, independently from biomes. For example, forests and deserts could form up on a hill without needing a special biome just for that.

• New ore distribution (see this chart)

• Large ore veins

• Integrated mountains, caves, and cave entrances

• Monsters will only spawn in complete darkness

Known issues

These issues are all addressed in the upcoming normal snapshot series and won't be fixed in the experimental snapshots.

• Low performance
• Nether terrain is messed up
• End pillars don't generate (however they do generate when you respawn the dragon...)

How do I get the experimental snapshot?

Installation

• Download this zip file

• Unpack the folder into your "versions" folder of your local Minecraft application data folder (see below if you are confused)

• Create a new launch installation in the launcher and select the "pending 1.18_experimental-snapshot-7" version

• Start the game and the remaining files will be downloaded

• Play in a new world! This version is not compatible with other snapshots!

Finding the Minecraft application data folder

• Windows: Press Win+R and type %appdata%\.minecraft and press Ok

• Mac OS X: In Finder, in the Go menu, select "Go to Folder" and enter ~/Library/Application Support/minecraft

• Linux: ~/.minecraft or /home/<your username>/.minecraft/

What about the previous Caves & Cliffs preview datapack?

These changes are too big for a datapack, that's why we're doing it in a separate experimental snapshot. So for now, the experimental snapshot serves the same purpose as the datapack did before.

Can I open old worlds in this experimental snapshot?

No, experimental snapshots can only open worlds that were created in the same version. Later on in the actual 1.18 release you will be able to open 1.17 worlds.

What about Bedrock?

An earlier version of experimental Caves & Cliffs world generation is available on Minecraft Bedrock. You can read about it here. We are working hard to get this new version of world generation to Bedrock betas soon.

How do I give feedback?

Use the feedback site or this Reddit post. 

We are mostly interested in feedback about the new world generation overall, and what it is like to play in it. We are also looking for feedback on the updated mob spawning. We changed so that mobs only spawn in complete darkness in order to make it easier to spawn-proof the new larger caves.

New feature requests are not so useful at this point, since the scope of the Caves & Cliffs update is already large enough and we want to focus on finishing the features that we've already announced.

Note that we don’t use the bug tracker for experimental snapshots.

When will these features show up in the normal snapshots?

1.18 snapshots will probably start sometime around September.

Ore distribution