Minecraft Snapshot Reverse Engineering

This is where I post my findings from looking at the source code for every new Minecraft snapshot. I document the exact details of how each feature works, and everything not found in the official changelogs.

You can usually expect a post within 1-2 days of the snapshot releasing.

Snapshot Posts

Minecraft 24w18a   04 May 2024

The first snapshot of the full 1.21 release is out! See the changelog.

Minecraft 1.20.6   29 Apr 2024

1.20.6 releases the critical fix from the last release candidate. See the changelog.

Minecraft 1.20.6-rc1   26 Apr 2024

A release candidate for 1.20.6 is out, fixing a critical issue. See the changelog.

Minecraft 1.20.5   23 Apr 2024

1.20.5 is out! See the changelog.

Minecraft 1.20.5-rc3   22 Apr 2024

Just one bug fix. See the changelog.

Minecraft 1.20.5-rc2   19 Apr 2024

Mojang, this is the fifth day in a row you’ve posted a snapshot. See the changelog.

Minecraft 1.20.5-rc1   18 Apr 2024

The first 1.20.5 release candidate is out, expecting a release next week. See the changelog.

Minecraft 1.20.5-pre4   17 Apr 2024

A very small pre-release this time. See the changelog.

Minecraft 1.20.5-pre3   16 Apr 2024

Pre-releases two days in a row! Now with even more bugfixes. See the changelog.

Minecraft 1.20.5-pre2   15 Apr 2024

Another pre-release with many bugfixes. See the changelog.

Minecraft 1.20.5-pre1   15 Apr 2024

The first 1.20.5 pre-release is out, tweaking potion effects and Ominous Trials. See the changelog.

Minecraft 24w14a   13 Apr 2024

Time to update those custom launchers. See the changelog.

Minecraft 24w14potato   12 Apr 2024

For this year’s April Fools snapshot, Mojang adds everything. See the changelog.

Minecraft 24w13a   31 Mar 2024

A massive snapshot adding the final 1.21 features. See the changelog.

Minecraft 24w12a   20 Mar 2024

This snapshot makes it easier to find trial chambers and create cursed videos. See the changelog.

Minecraft 24w11a   15 Mar 2024

A new snapshot adds a new way to deal absurd damage. See the changelog.

Minecraft 24w10a   06 Mar 2024

This snapshot adds new wolf variants! See the changelog.

Minecraft 24w09a   01 Mar 2024

This snapshot improves wolf armor and introduces data components. See the changelog.

Minecraft 24w07a   14 Feb 2024

This snapshot adds a highly-requested skeleton variant and fixes hoppers. See the changelog.

Minecraft 24w06a   09 Feb 2024

If fighting is sure to result in victory then you must fight! See the changelog.

Minecraft 24w05b   01 Feb 2024

Goodbye strength 255. See the changelog.

Minecraft 24w05a   31 Jan 2024

This snapshot unvaults the Vault. See the changelog.

Minecraft 24w04a   24 Jan 2024

Another snapshot adding tweaks to the armadillo and technical changes. See the changelog.

Minecraft 24w03b   18 Jan 2024

A surprisingly large b snapshot. See the changelog.

Minecraft 24w03a   18 Jan 2024

This snapshot reduces the spawn chunks and adds the long-requested transfer packet! See the changelog.

Minecraft 23w51b   18 Dec 2023

The armadillo was added. See the changelog.

Minecraft 1.20.4   07 Dec 2023

1.20.4 releases the critical fix from the last release candidate. See the changelog.

Minecraft 1.20.4-rc1   06 Dec 2023

A release candidate for 1.20.4 is out, fixing a critical issue. See the changelog.

Minecraft 1.20.3   05 Dec 2023

1.20.3 is out! See the changelog.

Minecraft 1.20.3-rc1   30 Nov 2023

The first 1.20.3 release candidate is out. See the changelog.

Minecraft 1.20.3-pre4   28 Nov 2023

Only two more bugfixes. See the changelog.

Minecraft 1.20.3-pre3   27 Nov 2023

As 1.20.3 approaches, this pre-release fixes more bugs. See the changelog.

Minecraft 1.20.3-pre2   22 Nov 2023

Another pre-release changes how wind charges behave in water. See the changelog.

Minecraft 1.20.3-pre1   20 Nov 2023

The first pre-release for 1.20.3 is out, adding tools for server resource packs and bugfixes. See the changelog.

Minecraft 23w46a   16 Nov 2023

The crafter and copper bulb were nerfed. See the changelog.

Minecraft 23w45a   13 Nov 2023

This massive snapshot adds Trial Chambers and the Breeze. See the changelog.

Minecraft 23w44a   01 Nov 2023

A smaller snapshot with some small improvements. See the changelog.

Minecraft 23w43b   27 Oct 2023

Fixes a few crashes from 23w43a. See the changelog.

Minecraft 23w43a   25 Oct 2023

A new 1.21 snapshot adds tick warping! See the changelog.

Minecraft 23w42a   19 Oct 2023

It’s here. See the changelog.

Minecraft 23w41a   11 Oct 2023

Decorated pots can now store items! See the changelog.

Minecraft 23w40a   04 Oct 2023

The first snapshot for 1.20.3 is out! See the changelog.

Minecraft 1.20.2   21 Sep 2023

1.20.2 is out! See the changelog.

Minecraft 1.20.2-rc2   18 Sep 2023

A small release candidate fixes villagers suffocating in minecarts. See the changelog.

Minecraft 1.20.2-rc1   15 Sep 2023

The first 1.20.2 release candidate is out, full release planned next week. See the changelog.

Minecraft 1.20.2-pre4   13 Sep 2023

Another snapshot with even more bugfixes. See the changelog.

Minecraft 1.20.2-pre3   12 Sep 2023

A few more bugfixes before the 1.20.2 release. See the changelog.

Minecraft 1.20.2-pre2   07 Sep 2023

A new 1.20.2 pre-release fixes bugs and reverts the recipe book changes. See the changelog.

Minecraft 1.20.2-pre1   05 Sep 2023

The first 1.20.2 pre-release reworks armorer and cartographer villagers. See the changelog.

Minecraft 23w35a   30 Aug 2023

Another snapshot with bug fixes. See the changelog.

Minecraft 23w33a   18 Aug 2023

This snapshot adds skin/name reporting and mob attack reach changes. See the changelog.

Minecraft 23w32a   13 Aug 2023

This snapshot brings vibration changes and many technical changes. See the changelog.

Minecraft 23w31a   12 Aug 2023

The first snapshot for 1.20.2 is out! See the changelog.

Minecraft 1.20.1   12 Jun 2023

1.20.1 is out! See the changelog.

Minecraft 1.20.1-rc1   09 Jun 2023

A 1.20.1 release candidate has been released, fixing some critical issues. See the changelog.

Minecraft 1.20   07 Jun 2023

1.20 is out! See the changelog.

Minecraft 1.20-rc1   31 May 2023

The first 1.20 release candidate wraps up development. See the changelog.

Minecraft 1.20-pre7   29 May 2023

This pre-release adds symbolic link validation. See the changelog.

Minecraft 1.20-pre6   25 May 2023

Yet another pre-release with some technical tweaks. See the changelog.

Minecraft 1.20-pre5   23 May 2023

A new pre-release inches closer to 1.20 with more bug fixes. See the changelog.

Minecraft 1.20-pre4   19 May 2023

A crash fix from the previous pre-release. See the changelog.

Minecraft 1.20-pre3   19 May 2023

Pre-release 3 fixes even more bugs. See the changelog.

Minecraft 1.20-pre2   16 May 2023

Another pre-release, another ancient bug fixed. See the changelog.

Minecraft 1.20-pre1   10 May 2023

The first 1.20 pre-release is out, adding universal dyeing and fixing an ancient bug. See the changelog.

Minecraft 23w18a   07 May 2023

A new snapshot adds telemetry tweaks and fixes an 11 year old bug. See the changelog.

Minecraft 23w17a   29 Apr 2023

New music, new advancements, and a new light engine! See the changelog.

Minecraft 23w16a   23 Apr 2023

This snapshot tweaks trail ruins and fixes the infamous chunk border lag spike. See the changelog.

Minecraft 23w14a   08 Apr 2023

Another snapshot is out with highly-requested bugfixes. See the changelog.

Minecraft 23w13a or b   08 Apr 2023

23w13a is out. Or is it 23w13b? Vote now! See the changelog.

Minecraft 23w13a   29 Mar 2023

A new 1.20 snapshot fixes bugs in the previous snapshot. See the changelog.

Minecraft 23w12a   26 Mar 2023

The first 1.20 update is out and definitely does not have “no more major features”. See the changelog.

Minecraft 1.19.4   14 Mar 2023

1.19.4 is out! See the changelog.

Minecraft 1.19.4-rc3   13 Mar 2023

Another release candidate prepares for a release tomorrow. See the changelog.

Minecraft 1.19.4-rc2   10 Mar 2023

Another release candidate fixes Guardian thorns. See the changelog.

Minecraft 1.19.4-rc1   09 Mar 2023

The first 1.19.4 release candidate is out. See the changelog.

Minecraft 1.19.4-pre4   08 Mar 2023

1.19.4 gets closer with even more bug fixes. See the changelog.

Minecraft 1.19.4-pre3   01 Mar 2023

This 1.19.4 pre-release contains a few more texture tweaks and bug fixes. See the changelog.

Minecraft 1.19.4-pre2   27 Feb 2023

Another 1.19.4 pre-release contains bug fixes and texture tweaks. See the changelog.

Minecraft 1.19.4-pre1   22 Feb 2023

The first 1.19.4 pre-release is here with lots of bug fixes. See the changelog.

Minecraft 23w07a   19 Feb 2023

This massive snapshot adds cherry trees, archaeology, and the Sniffer! See the changelog.

Minecraft 23w06a   08 Feb 2023

A new 1.19.4 snapshot adds efficient ways to display text, blocks, and items! See the changelog.

Minecraft 23w05a   01 Feb 2023

A new 1.19.4 snapshot adds armor trims to leather armor. See the changelog.

Minecraft 23w04a   25 Jan 2023

Another 1.19.4 snapshot is out, bringing an overhaul to smithing and armor trims! See the changelog.

Minecraft 23w03a   19 Jan 2023

The first snapshot for 1.19.4 is out! See the changelog.

Minecraft 1.19.3   07 Dec 2022

1.19.3 is out! See the changelog.

Minecraft 1.19.3-rc3   06 Dec 2022

1.19.3 has been delayed by one day. See the changelog.

Minecraft 1.19.3-rc2   05 Dec 2022

The second and probably final 1.19.3 release candidate is out. See the changelog.

Minecraft 1.19.3-rc1   01 Dec 2022

The first 1.19.3 release candidate is out. See the changelog.

Minecraft 1.19.3-pre3   29 Nov 2022

Another pre-release is out with some bugfixes. See the changelog.

Minecraft 1.19.3-pre2   24 Nov 2022

Another pre-release is out with some bugfixes. See the changelog.

Minecraft 1.19.3-pre1   24 Nov 2022

The first 1.19.3 pre-release is here with custom player head sounds. See the changelog.

Minecraft 22w46a   24 Nov 2022

A new snapshot is out, adding playable mob sounds. See the changelog.

Minecraft 22w45a   18 Nov 2022

A new snapshot with even more creative inventory tweaks. See the changelog.

Minecraft 22w44a   16 Nov 2022

Another snapshot focusing on quality-of-life changes. See the changelog.

Minecraft 22w43a   15 Nov 2022

Another 1.19.3 snapshot is here, fixing bugs from 22w42a. See the changelog.

Minecraft 22w42a   04 Nov 2022

The first 1.19.3 (and 1.20) snapshot is here! See the changelog.

Minecraft 1.19.1-pre3   06 Jul 2022

A new pre-release is out with some minor fixes. See the changelog.

Minecraft 1.19.1-pre2   30 Jun 2022

Mojang has delayed 1.19.1 and released a second pre-release. See the changelog.

Minecraft 1.19.1-rc1   23 Jun 2022

The first 1.19.1 release candidate is here, adding more context to reports See the changelog.

Minecraft 1.19.1-pre1   21 Jun 2022

The first 1.19.1 pre-release is here, adding permanent multiplayer bans. See the changelog.

Minecraft 22w24a   19 Jun 2022

The first 1.19.1 snapshot is here, adding player chat reporting. See the changelog.

Minecraft 1.19   07 Jun 2022

The Wild Update is here! See the changelog.

Minecraft 1.19-rc2   03 Jun 2022

The second release candidate is out with very few changes. See the changelog.

Minecraft 1.19-rc1   02 Jun 2022

The first release candidate is out. See the changelog.

Minecraft 1.19-pre5   01 Jun 2022

Another pre-release with some game event changes. See the changelog.

Minecraft 1.19-pre4   30 May 2022

A small pre-release with a few bug fixes. See the changelog.

Minecraft 1.19-pre3   25 May 2022

The Warden just got its final buff. See the changelog.

Minecraft 1.19-pre2   23 May 2022

Another 1.19 pre-release is out. See the changelog.

Minecraft 1.19-pre1   18 May 2022

The first 1.19 pre-release is out! See the changelog.

Minecraft 22w19a   14 May 2022

A new snapshot with lots of technical changes. See the changelog.

Minecraft 22w18a   04 May 2022

Another smaller snapshot with some allay and warden tweaks. See the changelog.

Minecraft 22w17a   27 Apr 2022

A smaller snapshot this time, adding goat horns. See the changelog.

Minecraft 22w16b   26 Apr 2022

Another snapshot is out, adding a new music disc and some random changes. See the changelog.

Minecraft 22w15a   13 Apr 2022

This snapshot gives the warden a massive buff. See the changelog.

Minecraft 22w14a   12 Apr 2022

This snapshot brings the new mangrove swamp biome. See the changelog.

Minecraft 22w13oneblockatatime   01 Apr 2022

This snapshot may be a joke, but the automation and speedrunning potential is not! See the changelog.

Minecraft 22w13a   01 Apr 2022

The allay is here! See the changelog.

Minecraft 22w12a   25 Mar 2022

The second 1.19 snapshot is out, adding the Warden. See the changelog.

Minecraft 22w11a   16 Mar 2022

The first 1.19 snapshot is out, and update suppression is now patched. See the changelog.

Minecraft 1.18.2   28 Feb 2022

1.18.2 is now out. See the changelog.

Minecraft 1.18.2-rc1   25 Feb 2022

The first 1.18.2 release candidate is out. See the changelog.

Minecraft 1.18.2-pre3   23 Feb 2022

The third 1.18.2 pre-release brings more bug and crash fixes. See the changelog.

Minecraft 1.18.2-pre2   21 Feb 2022

The second 1.18.2 pre-release is out. See the changelog.

Minecraft 1.18.2-pre1   18 Feb 2022

Three snapshots in a row!? 1.18.2 is coming up soon. See the changelog.

Minecraft 1.19 Experimental Snapshot 1   18 Feb 2022

Here we go… the first snapshot for 1.19 is out! It is an experimental snapshot, you must download it from the changelog.

Minecraft 22w07a   16 Feb 2022

Another snapshot for 1.18.2 adds biome customization and some sneaky mob spawning changes. See the changelog.

Minecraft 22w06a   09 Feb 2022

Another snapshot for 1.18.2 is out with many hidden changes. See the changelog.

Minecraft 22w05a   02 Feb 2022

Another snapshot for 1.18.2 is out. See the changelog.

Minecraft 22w03a   19 Jan 2022

The first snapshot of 2022 is here. See the changelog.

Minecraft 1.18.1   10 Dec 2021

1.18.1 is now out. See the changelog.

Minecraft 1.18.1-rc3   09 Dec 2021

1.18.3-rc3 fixes a critical security issue. See the changelog.

Minecraft 1.18   30 Nov 2021

The Caves and Cliffs Update Part 2 is finally out! See the changelog.

Minecraft 1.18.1-pre2   16 Nov 2021

This second 1.18 pre-release is out, now with Java 17! See the changelog.

Minecraft 21w44a   03 Nov 2021

21w44a is out now, adding optimizations and the ability to opt-out of player listings. See the changelog.

Minecraft 21w43a   27 Oct 2021

21w43a is out and adds blending of old worlds. See the changelog.

Minecraft 21w42a   20 Oct 2021

Another 1.18 snapshot is out, featuring a new music disc! See the changelog.

Minecraft 21w41a   13 Oct 2021

This snapshot officially changes the random number generator used for worldgen. See the changelog.

Minecraft 21w40a   07 Oct 2021

A new snapshot is out, buffing copper ore. See the changelog.

Minecraft 21w39a   29 Sep 2021

The third 1.18 snapshot is out, and old worlds can finally be opened again. See the changelog.

Minecraft 21w37a   15 Sep 2021

The first non-experimental 1.18 snapshot is out! See the changelog.

Minecraft 1.18 Experimental Snapshot 3   10 Aug 2021

The third experimental snapshot for 1.18 is out, with some major mob spawning changes! See the changelog.

Minecraft 1.18 Experimental Snapshot 1   13 Jul 2021

The first snapshot for 1.18 is out! It is an experimental snapshot, you must download it from the changelog.

Minecraft 1.17.1   06 Jul 2021

Minecraft 1.17.1 is out! There are no new changes since 1.17.1-rc2. See the changelog.

Minecraft 1.17.1-rc2   05 Jul 2021

The second release candidate fixes some critical issues. See the changelog.

Minecraft 1.17.1-rc1   01 Jul 2021

The first release candidate for 1.17.1 is out, there are no new mechanics to investigate. See the changelog.

Minecraft 1.17.1-pre3   30 Jun 2021

This pre-release buffs adds a couple bugfixes, there are no new mechanics to investigate. See the changelog.

Minecraft 1.17.1-pre2   29 Jun 2021

This pre-release buffs diamond ore, nerfs emerald ore, and introduces a couple stealth fixes. See the changelog.

Minecraft 1.17.1-pre1   18 Jun 2021

The first 1.17.1 pre-release changes axolotl and goat breeding mechanics, and a buff to drowned copper farms and powder snow farms! See the changelog.

Minecraft 1.17   08 Jun 2021

The Caves and Cliffs Update Part 1 is finally out! See the changelog.

Minecraft 1.17-rc2   07 Jun 2021

The second (and probably final) pre-release is out. The changelog says, “fixed a few critical issues”, but now we know what those critical issues are. See the changelog.

Minecraft 1.17-rc1   04 Jun 2021

The first release candidate is out! As expected, it has no new features to investigate. See the changelog.

Minecraft 1.17-pre5   03 Jun 2021

The pre-releases are wrapping up, this one has no new features to investigate. See the changelog.

Minecraft 1.17-pre4   02 Jun 2021

The fourth pre-release fixes a few more bugs. See the changelog.

Minecraft 1.17-pre3   01 Jun 2021

The third pre-release changes glow squid spawning conditions and fixes more bugs. See the changelog.

Minecraft 1.17-pre2   01 Jun 2021

The second pre-release is out and so is the release date! See the changelog.

Minecraft 1.17-pre1   27 May 2021

The first 1.17 pre-release is out! See the changelog.

Minecraft 21w20a   19 May 2021

This snapshot adds a new way to farm hanging roots, new narrator features, and plenty of bugfixes. See the changelog.

Minecraft 21w19a   12 May 2021

This snapshot makes candles, bundles, and sculk sensors command-only, and upgrades Java to Java 16. See the changelog.

Minecraft 21w18a   05 May 2021

Another smaller snapshot that makes screaming goats use their ram attack more often. See the changelog.

Minecraft 21w17a   28 Apr 2021

A smaller snapshot with a copper ore buff and even more tweaks to the raw ore block textures. See the changelog.

Minecraft 21w16a   21 Apr 2021

This snapshot adds dripstone and azalea growth, as well as even more raw ore texture tweaks. See the changelog.

Minecraft 21w15a   14 Apr 2021

This snapshot adds goat ramming, raw ore blocks, and marker entities. The Caves & Cliffs update was also split in two. See the changelog and the announcement.

Minecraft 21w14a   07 Apr 2021

Now you can use fortune on iron, gold, and copper ore! A simple snapshot, but a massive game changer. See the changelog.

Minecraft 21w13a   31 Mar 2021

This snapshot adds goats, a darker splash screen, axolotl spawns, and the light block! See the changelog.