Datapack Codex

Java Edition 1.21.9 Release Candidate 1

Minecraft Wiki article. Categories: Java_Edition_versions, Java_Edition_1.21.9_release_candidates, Java_Edition_release_candidates_released_in_2025, Java_Edition_release_candidates, Pages_with_YouTube_videos

📌 Mirrored from Minecraft Wiki

This article is reproduced from Java Edition 1.21.9 Release Candidate 1 on the Minecraft Wiki. Mirrored from revision 3660393. It is licensed CC BY-NC-SA 3.0 by the Minecraft Wiki contributors — not under the Codex’s CC BY-SA 4.0, and it may not be used commercially. Edits belong upstream, not here.

On this page
Minecraft 1.21.9 Release Candidate 1
1.21.9-rc1.jpg: Infobox image for Minecraft version 'Minecraft 1.21.9 Release Candidate 1'
Java Edition 1.21.9 Release Candidate 1.png: Infobox image for Minecraft version 'Minecraft 1.21.9 Release Candidate 1'
{
    "title": "Minecraft 1.21.9 Release Candidate 1",
    "images": [
        "1.21.9-rc1.jpg",
        "Java Edition 1.21.9 Release Candidate 1.png"
    ],
    "rows": [
        {
            "field": "''(link to Java Edition article, displayed as Java Edition)''",
            "label": "(link to Edition article, displayed as Edition)"
        },
        {
            "field": "September 25, 2025",
            "label": "Release date"
        },
        {
            "field": "(link to Release Candidate article, displayed as Release Candidate)",
            "label": "(link to Version types article, displayed as Type)"
        },
        {
            "field": "(link to Java Edition 1.21.9 article, displayed as 1.21.9)",
            "label": "Release candidate for"
        },
        {
            "field": "[https://piston-data.mojang.com/v1/objects/4cf039bc84f306d0f18e1ebd2e928af82292e8d9/client.jar Client] ([https://piston-meta.mojang.com/v1/packages/93fdb571a5b1cd0f2a233075e2e2cf2dd95cf817/1.21.9_Release_Candidate_1.json .json])<br />[https://piston-data.mojang.com/v1/objects/12b937eebe1a732f9dd1db9ae6443070e1d30045/server.jar Server]",
            "label": "(link to Tutorial:Installing a version#Manual version installation article, displayed as Downloads)"
        },
        {
            "field": "[https://piston-data.mojang.com/v1/objects/31c9f5458d11131601e5ff84b39717a512d4d04c/client.txt Client]<br />[https://piston-data.mojang.com/v1/objects/2f6276ff7c33ebb03ac9f985f42cb883fc93b14c/server.txt Server]",
            "label": "(link to Obfuscation map article, displayed as Obfuscation maps)"
        },
        {
            "field": " <span title=\"decimal\">dec</abbr>: </span>1073742097<br /> <span title=\"hexadecimal\">hex</abbr>: </span>40000111",
            "label": "(link to Protocol version article, displayed as Protocol version)"
        },
        {
            "field": "4553",
            "label": "(link to Data version article, displayed as Data version)"
        },
        {
            "field": "69.0",
            "label": "<span normal;\">(link to Pack format#List of pack formats article, displayed as Resource pack format)</span>"
        },
        {
            "field": "88.0",
            "label": "<span normal;\">(link to Pack format#List of pack formats article, displayed as Data pack format)</span>"
        },
        {
            "field": "<span class=\"plainlinks\">[https://en.wikipedia.org/wiki/Java_version_history#Java_SE_21_.28LTS.29 Java SE 21]</span>",
            "label": "<span normal;\">Minimum Java version</span>"
        }
    ],
    "invimages": [],
    "footer": "<table auto; word-break: break-word;\">\n<tr inherit;\">\n<td 0.4em\" >[[Java Edition  1.21.8|<span  1.21.8]]</td>\n<td 0.4em\">'''[[Java Edition 1.21.9|1.21.9]]'''</td>\n<td 0.4em\" rowspan=\"2\">[[Java Edition  1.21.10|  1.21.10 <span inherit;\">\n<td 0.4em\">\n[[Java Edition  1.21.9 Pre-Release 4|◄   1.21.9 Pre-Release 4]]\n</td>\n<td 0.4em\">''' 1.21.9 Release Candidate 1'''</td>\n</tr>\n</table>"
}

1.21.9 Release Candidate 1 (known as 1.21.9-rc1 in the launcher) is the first and only release candidate for Java Edition 1.21.9, released on September 25, 2025.[1]

Fixes

2 issues fixed

From the 1.21.9 development versions

  • MC-302243 – Creakings can spawn with the spawnMonsters game rule set to false.

From the previous development version

  • MC-302278 – The texture in the middle of conduits is upside down.

Trivia

  • This version has the same protocol version number as 25w41a. The two versions are not actually compatible; 1.21.9-rc1 throws a "Network Protocol Error" message when attempting to join a 25w41a world, and 25w41a crashes when attempting to join a 1.21.9-rc1 world.

Videos

Video made by slicedlime:

References

  1. ↑ "Minecraft 1.21.9 Release Candidate 1" – Minecraft.net, September 25, 2025.

Sources