The Bug
The specific superflat presets which are intentionally designed to resemble the Default world generation have not been changed despite the default world generation being significantly changed. Namely, you spawn 64 blocks too low now because an additional 64 blocks of stone do not spawn to compensate for the new world depth. (Additionally, Tunneler's Dream could have even more than 64 layers of stone added being that it is designed to take up most of the build limit for... tunneling. This particularity may not be a bug but it would make sense.)
Some, such as Classic Flat, should not be changed, as well as Bottomless Pit and The Void. Redstone Ready and Water World do not matter either way.
This can be fixed by the player by changing the presets, but this is not ideal since there is no save function for custom presets, and it essentially breaks the purpose of having presets.
How to fix
Update the old settings to the following settings to comply with the 1.18 update:
Tunnelers' Dream
minecraft:bedrock,64*minecraft:deepslate,230*minecraft:stone,5*minecraft:dirt,minecraft:grass_block;minecraft:windswept_hillsOverworld
minecraft:bedrock,64*minecraft:deepslate,59*minecraft:stone,3*minecraft:dirt,minecraft:grass_block;minecraft:plainsSnowy Kingdom
minecraft:bedrock,64*minecraft:deepslate,59*minecraft:stone,3*minecraft:dirt,minecraft:grass_block,minecraft:snow;minecraft:snowy_plainsDesert
minecraft:bedrock,64*minecraft:deepslate,3*minecraft:stone,52*minecraft:sandstone,8*minecraft:sand;minecraft:desertLinked issues
is duplicated by 3
Comments
violine1101
[Mod] LateLag
Not a duplicate. Reopened and confirmed.
Adrian Östergård
This is a feature request.
migrated
The lowering by 64 blocks results in slimes overrunning overwork, snowy kingdom, and desert. No ponds on them but more lava ponds. No sand, gravel, reeds. Their is water only in villages. Some of us do use these worlds for specific game types. Yes the fix proposed by Brevort above is a feature request but is should have been obvious that just moving them down would not work. Deep slate is one option. I've experimented with granite. Please fix.
Brevort
Thank you for your report!
We're tracking this issue in MC-214951, so this ticket is being resolved and linked as a duplicate.
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