(1.19.2) When creating a biome modification that targets cave biomes, the spawn settings are ignored and no injected spawns are applied:

iomeModifications.addSpawn(
                    biomeSelectionContext -> {
                        return biomeSelectionContext.getBiomeRegistryEntry().isIn(ConventionalBiomeTags.CAVES);
                    }, 
                    SpawnGroup.AMBIENT, 
                    EntityType.WOLF, 
                    100, 
                    2, 
                    4
            );

You would expect a large amount of wolves spawning in the cave biomes now - yet this is not the case.

/tp @e[type=wolf,dy=106] @s (I am standing on y=-46 when running this command, max y is 64

This command will teleport all of the wolves spawned in the cave biomes to the player.

As you can see, there are no wolves in the biomes.

Going to be honest, never knew about these spawn restrictions. Thanks 👍

I think you need to look at WolfEntity.canSpawn() or more accurately the SpawnRestriction class.
You won't find many grass and snow blocks above light level 8 in caves. :-)
https://github.com/misode/mcmeta/blob/data/data/minecraft/tags/blocks/wolves_spawnable_on.json

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