This is because the only mobs that spawn in soul sand valleys are skeletons, Minecraft limits the mob spawning in soul sand valleys and warped forests because they want it to appear more sparse. This means that you don't have to spawnproof these biomes for wither skeleton farms, as this is what this mechanic is most useful for mainly.
Whimis_Call
This is because the only mobs that spawn in soul sand valleys are skeletons, Minecraft limits the mob spawning in soul sand valleys and warped forests because they want it to appear more sparse. This means that you don't have to spawnproof these biomes for wither skeleton farms, as this is what this mechanic is most useful for mainly.