[MC-3524] Structure related mobs do not spawn in flat type world generation Created: 20/Nov/12  Updated: 18/Jul/22  Resolved: 18/Feb/22

Status: Resolved
Project: Minecraft: Java Edition
Component/s: None
Affects Version/s: Minecraft 1.4.5, Minecraft 1.5, Minecraft 1.6.4, Minecraft 1.7.2, Minecraft 1.8, Minecraft 1.8.1-pre3, Minecraft 1.8.4, Minecraft 1.8.8, Minecraft 15w45a, Minecraft 1.10.2, Minecraft 1.11.2, 1.15.1, 1.15.2, 20w12a, 20w16a, 1.16 Pre-release 2, 1.16 Release Candidate 1, 1.16, 1.16.1, 20w28a, 1.16.3, 21w07a, 21w15a, 21w20a, 1.17 Pre-release 2, 1.17, 1.17.1 Release Candidate 1, 1.17.1, 21w38a, 1.18, 1.18.1, 22w06a
Fix Version/s: 1.18.2 Pre-release 1

Type: Bug
Reporter: Fredrik Olsson Assignee: Unassigned
Resolution: Fixed Votes: 38
Labels: None

Attachments: PNG File 2012-11-20_08.36.19.png     PNG File generator_default.png     PNG File generator_flat.png    
Issue Links:
Duplicate
is duplicated by MC-59314 Guardians not spawning on superflat w... Resolved
is duplicated by MC-147360 Pillagers don't spawn near outposts i... Resolved
is duplicated by MC-169728 Structure related mobs do not spawn i... Resolved
is duplicated by MC-169938 Superflat does not spawn Pillagers Resolved
is duplicated by MC-233201 Pillagers don't spawn near outpost. Resolved
is duplicated by MC-233813 Witch huts in custom superflat preset... Resolved
is duplicated by MC-1582 Witches do not spawn in superflat worlds Resolved
CHK:
Confirmation Status: Confirmed
Game Mode: Creative
Category:
Mob spawning, Structures
Mojang Priority: Important

 Description   

Structure related mobs can not spawn in superflat worlds.
This is true for:

  • Pillager
  • Witches
  • Guardians

Steps taken to confirm this:

Forward Confirmation

  1. Generated World on any Seed with Superflat (flat) World Generation and included all available structures (default spawn ratio)
  2. Using admist and /locate to find nearest structure, teleport to it, and confirm no spawning
  3. Save and exit.
  4. Using NBTExplorer change world generation type from 'flat' to 'default'
  5. Join world and confirm spawning entities
  6. Confirm changed world-gen by loading new chunks

Backward Confirmation

  1. Generated new default World on any Seed
  2. Using /locate to find and teleport to nearest structure. Confirm through admist as well.
  3. Save and exit.
  4. Using NBTExplorer change world generation type from 'default' to 'flat'
  5. Join world and kill all Entities (except player) to confirm no spawning entities.
  6. Confirm changed world-gen by loading new chunks

In addition, seed-changes were tested, as well as importing confirmed-working chunks into superflat world and manually creating structures through NBTExplorer.

 

In all these cases structure entities consistently did not spawn while level.dat contained 'flat' - type world generation.

 



 Comments   
Comment by Daniel Jansson [ 06/Feb/22 ]

Still the case in 1.18.1

Comment by W_V [ 21/May/21 ]

Can confirm for 21w20a

Comment by W_V [ 09/Jul/20 ]

In 1.16.1 and 20w28a

Comment by Alexis Evelyn [ 08/Jun/20 ]

Can confirm, this is still an issue for 1.16 pre-2. I spent a few hours pouring over nbt data trying to figure out why my outpost wasn't working and weeded it out to world type. Also, I tried a superflat preset explicitely telling the game to generate the outposts to find out it didn't work anyway.

Comment by W_V [ 22/Mar/20 ]

Confirmed for 1.15.2 and 20w12a

Comment by Jack Flint [ 11/Jan/20 ]

Testing regarding this issue, this issue is superseded by issue MC-169728

Edit: No longer the case, as moderator merged posts.

Comment by Dracconis69 [ 15/Sep/19 ]

Can confirm that this issue is still present in all versions after the OP's reported versions. For creators trying to make a superflat void world for their Skyblock maps only regular mobs will spawn and Guardian Temples will not even spawn in.

Comment by Smokey95dog [ 05/Nov/15 ]

Still an issue in 1.8.8 and the newest 1.9 snapshot 15w45a.

Comment by Fredrik Olsson [ 04/May/15 ]

Still an issue in 1.8.4

Comment by Someone 3x7 [ 18/Feb/15 ]

Still an issue in 1.8.2-pre7

Comment by Brad Corbin [ 25/Oct/14 ]

Seems similar in many ways to MC-59314 (Guardians not spawning on superflat worlds).

Different details, also much easier to test (just create a superflat world using preset "Water World").

Comment by Brad Corbin [ 25/Oct/14 ]

Yes, confirmed that it is still a problem for 1.8.1 Prerelease 3

Above directions still apply, use the following for superflat preset:
3;2*minecraft:bedrock,60*minecraft:dirt,minecraft:stone_slab;6;biome_1

Comment by Galaxy_2Alex [ 24/Oct/14 ]

Is this still a concern in the current Minecraft version 1.8.1 Prerelease 3 / Launcher version 1.5.3 or later? If so, please update the affected versions in order to best aid Mojang ensuring bugs are still valid in the latest releases/pre-releases.

Comment by Brad Corbin [ 02/May/14 ]

Can confirm, still a problem in release 1.7.9.

I also was able to confirm that this is directly a result of the world generation settings. I generated a flatland using the settings in the description above, normal mobs spawned (see image generator_flat.png).

I then used NBTExplorer and edited the "generatorName" value in level.dat from "flat" to "default". After reloading the world, only witches spawned (see generator_default.png).

Comment by Galaxy_2Alex [ 21/Jan/14 ]

Is this still a concern in the current Minecraft version 1.7.4 / Launcher version 1.3.8 or later? If so, please update the affected versions in order to best aid Mojang ensuring bugs are still valid in the latest releases/pre-releases.

Comment by Fredrik Olsson [ 29/Oct/13 ]

Still a bug in 1.7.2

The strange part is that the "area" in Temple.dat under the data folder is generated and looks to be correct.
But the flatland code seems to ignore that data.

Comment by Fredrik Olsson [ 18/Mar/13 ]

Tested in 1.5 and the bug is still there!

Comment by Tails [ 15/Mar/13 ]

Is this still a concern in the current Minecraft version? If so, please update the affected versions in order to best aid Mojang ensuring bugs are still valid in the latest releases/pre-releases.

Comment by Tails [ 06/Dec/12 ]

Removed "CLONE" in the title.

Comment by Chalmes (Jon) [ 20/Nov/12 ]

You've convinced me, confirmed

Poking in the code it seems that yes there is a witch spawned by the world generator by default when the hut is initially created, but after that, only the regular mobs would spawn in there. I tried deconstructing the hut and rebuilding the floor at different heights, but nothing would force another witch to spawn there.

Comment by Fredrik Olsson [ 20/Nov/12 ]

The witch pressent in the pic "Can't reproduce in 1.4.5.jpg" is generated with the hut and not spawned in in the hut.

In the screenshot i posted a skeleton has spawned in the hut, and that only happens in flat worlds.
In normal worlds the only mob that can spawn in a hut is the witch!

So i still claim this to be a bug.

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