Uploaded October 2025 | Updated September 2026, 1 week ago

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Minecraft 1.21.9 brings us plenty of new technical functionality in new Pack versions - including Mannequin entities! Here's a comprehensive guide to all the news! #minecraftemployee

This guide applies for Minecraft Java Edition. Technical details are unlikely to apply to Bedrock.

slicedlime works as a Tech Lead for Minecraft at Mojang, but the YouTube and Twitch channels are personal projects run entirely in his spare time. This is an unofficial update video that aims to be the most comprehensive guide possible. Official announcement: minecraft.net/en-us/article/minecraft-java-edition-1-21-9

Gameplay News: youtu.be/sJdWQXbtSA8

Introduction: 0:00
Pack Formats: 0:20
Mannequins: 2:09
Profile Components: 3:04
Mannequin Data: 5:25
Text Components: 6:28
Commands: 7:51
Loot Item Functions: 10:39
Item Components: 11:03
Entities and Data: 11:12
Game Rules: 11:50
Enchantment Effects: 12:32
Particles: 12:54
Custom Worlds: 13:21
Structures and Jigsaws: 13:59
Tags: 14:26
Resource Packs: 15:20
Shaders: 15:44
Thank You: 16:09

Thank you to the helper crew! Bl4ckscor3, EpicGamerX125, JochCool & Magnar Akatsimi

Music by zircon (https://zirconstudios.bandcamp.com)
- Photosynthesis
- Unity
- Wasteland
- Tidal Glide

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#minecraft #news