Do you want to create a large house or big redstone machine but you often run out of free space? Well, this world is just for you! Unlike flat world type, this world is just a normal infinite world but with a large flat area!
I created some worlds with random seeds. This one was perfect. Then I erased some small hills with command /execute @p ~ ~ ~ fill ~10 ~10 ~10 ~ ~ ~ air.
In some places there was a stone floor. I replaced it with the command /execute @p ~ ~ ~ fill ~10 ~-1 ~10 ~ ~-1 ~ grass.
This world is perfect for your buildings. It has a lot of space. You can build a very huge house and several farms too!
There are also these huge amplified mountains where you can build an underground base! This world also has a little space next to the mountains. You can build some sort of entrance to insides.