The Minecraft 1.17 update contains a rather big change to the overworld, the place where the players spend most of their time. Specifically, terrain generation has undergone a significant change in that mountain and cave generation will be revolutionized, and new mobs and blocks were added.

Mountains, something players have been complaining for ages about, have been updated. Instead of the terrain algorithm which sometimes generated floating blocks and sudden changes in terrain, mountains are said to be generated much more realistically, with better landscapes and their own unique mobs: goats. Although it is not specified what the goat drops, the goat is a mob that attacks nearby mobs, and players can also breed them. It also has an impressive jump height of five.

Caves are also receiving an update. For one, there will be improved generations, which means that caves with generally defined structures will now be spawned, and new entities will be developed just for the cave. There is a new light source, called a cave candle, that acts like a sea pickle in that the player can collect them and place up to four of them on one block, and the more there are the lighter it is. They only spawn in caves. 

There are also multiple new types of caves. There are Dripstone caves, Lush caves, and mesh cave varieties.

Dripstone caves will be the most massive variety, with stalactites and stalagmites added as new features. They will also be flooded and contain a great variety of ores. Stalactites and stalagmites also are its own unique block, and they deal damage when the player lands on them.

Lush caves generate below azalea trees, which are trees with unique root-dirt blocks that mark the location of these caves. They come with their own unique vegetation, including tall grass, glow berries, dripleaf plants, spore blossoms, moss blocks, moss blankets, azalea roots, and azalea saplings. They can spawn axolotos, a reptile-like mob that can be tamed by putting it in a bucket. The mob in question also gains the regeneration effect when hurt.

The vegetation also has unique properties. The glow berries (that come in vine form) are a light source and produce edible berries. The dripleaf plant is a plant that can briefly act as scaffolding, making the player fall after standing for two seconds on it. The spore blossom can be planted on ceilings and send particles with an unknown effect downward when “opened” through interaction. Moss blocks are less unique, being merely blocks. The moss blanket is basically a carpet variety of moss blocks.

Mesh caves are caves that are large and tunnel-like, and they are confirmed by developers to have a catacomb style of branching cave sections.

There is a new small cave called the geode. It can spawn amethyst geodes, blocks with amethyst crystals growing off of it. Once they reach their mature stage, the player can harvest it to craft some new items like telescopes and other unconfirmed items.

There is one last new biome that is similar to a cave, but far deadlier. Inside, a mob known as the Warden will lurk in the shadows, being a mob that only detects the player based on movement and not on visual data. Players can press down the sneak button to get past the mob. This mob is about as tough as an iron golem but deals almost twice the damage, making it one of the heaviest hitters in the game (other than creeper explosions and the ender dragon). This biome will also allow candles to spawn, and unique blocks such as skulk blocks and skulk sensor blocks that can detect movement and give off a particle effect when movement is detected.

There are numerous new items that can be crafted, but Mojang is also introducing a new ore. Copper has been added to the game, and can be crafted into objects like lightning rods, telescopes, blocks, stairs, and slabs. Interestingly enough, it is the only metal in the game that can rust, slowly changing color through a variety of stages when the weather progresses. Copper is also used to craft telescopes, which can allow the player to see the part of the landscape the telescope is pointed at with greater detail.

A new resurgence in Minecraft updates, from 1.13 to 1.16, all of which gave new rise to the game’s popularity and relevance, are making the community a lot more active.

“The features added to caves will allow for a more engaging experience for cave explorers and will add details that many players have wanted for a long time. I’m really looking forward to playing on the new update too,” sophomore Raghav Tirumale said.

All information from https://minecraft.gamepedia.com/Java_Edition_1.17.