Pangaea

Image made with Distant Horizons mod.

This datapack replaces the vanilla overworld with one huge island surrounded by an endless ocean and occasional tiny mushroom islands using the new Density Functions added in 26.3.

Due to the world's limited nature, there is also a function to tell you whether a world contains every biome. If the function fails, you can always make a new world with a different seed and try again.

/function pangaea:check_biomes