Generation in specific Biomes

[AppliedOnce]

Hi, I just wondered if there is a way to add generation to specific biomes, like having pyramids spawn only in desert biomes.

 

And if that is possible, is it possible to make a mob only spawn inside a custom structure?

[SchemingWeasels]

As far is i know, you can make structures only spawn on certain blocks, but im not too sure how to code for certain biomes. But i do know that you can make custom mobs spawn in certain biomes 

[AppliedOnce]

Yeah, I know how to make a mob spawn in certain biomes, and I know how to make structures. I just don't know how to make a structure generate in only one biome, if that is possible. And for the mob part, I said spawn in or near a custom structure.