mojira.dev
MC-296311

TNT touching water will destroy blocks and damage entities but will ignore decorative entities

Resolved
Fixed
48

Following the fix of MC-3697, TNT will no longer destory decorative entities if the TNT is submerged in water. I can only assume this was done with the intention of making explosions interact with decorative entities the same way they do with blocks. However, if a TNT is touching water but the explosion does not originate in water, then the explosion will destroy blocks but not damage decorative entities. If the intent was to make explosions interact with decorative entities the same way they do with blocks, then there is a discrepency between their behavior.

Steps to reproduce:

  1. Place some blocks and drop some items so that they will be destroyed by the tnt summoned in step 2.

  2. Summon a TNT entity that is just barely touching a water column, as shown in the attached video.

  3. Observe that when the TNT explodes, blocks get broken but decorative entities do not.

Relates to: MC-3697 MC-279003 MC-280273

Environment

macOS 15.4 Sequoia
Java 21.0.3

Attachments

1_21_water_tnt_issue.mp4
25w16a_water_tnt_issue.mp4
overpowered_tree_farm.mp4
Screen Recording 2025-04-06 at 11.22.39 AM.mov

Comments 6

can confirm 1.21.5

can confirm 1.21.4
pretty sure it’s an issue since 1.21.2 when MC-3697 was resolved

Seems to be true. Will be voting.

For those who prefer using commands to reproduce the issue:

  1. In creative mode, fly a good bit upwards and look towards positive x/z

  2. /fill ~2 ~-3 ~2 ~4 ~-3 ~4 minecraft:obsidian

  3. /fill ~2 ~-2 ~4 ~4 ~-2 ~4 minecraft:slime_block

  4. /summon minecraft:armor_stand ~3 ~-2 ~3

  5. /summon pig ~2 ~-1 ~4 {Health:1,NoAI:1b}

  6. /summon minecraft:item ~4 ~-2 ~2 {Item:{id:"minecraft:magma_block",count:64}}

  7. /setblock ~2 ~-2 ~2 minecraft:water strict

  8. /execute positioned ~2 ~-1 ~2 align xyz run summon minecraft:tnt ~1.1 ~1 ~1.1 {Fuse:600}

Notice how the pig dies and the slime blocks are destroyed while the items and armor stand are unaffected

Can confirm since 24w33a. Must say it’s odd the tnt does no damage to decorative entities even if it’s just slightly touching the water, and also even less sense that items are included as decorative entities here.

Can replicate in 25w16a.
This issue is worse than described in the report for several reasons:

  • This behavior is very exploitable, here is an example of a tree farm concept someone made with this behavior (here it specifically relies on the fact that items dont get damaged by tnt explosions anymore).
    As you can see - its completely overpowered even by TMC standards.

    [media]

  • This issue somewhat affects cannon tech, as its no longer possible to accelerate item entities when blocks are shielded from explosions with water. Here are 2 examples:

    • 1.21.0 (items get accelerated):

      [media]

    • 25w16a (items dont get accelerated):

      [media]

GaRLic_BrEd_

(Unassigned)

Community Consensus

Platform

Important

Entities

1.21.5

25w20a

Retrieved