Sunflower Plains don't spawn Villages or animals like Plains do. I would expect Sunflower Plains to act exactly the same as Plains other than the addition of the sunflowers themselves.
MC-51188
Sunflower Plains don't spawn Villages or animals
Resolved
Duplicate
0
The mob spawning is a duplicate of MC-49742, I would suggest commenting and following there.
The village spawning is only in normal plains (and deserts, savannas), Sunflower Plains is a different biome.
Please put only one bug report in each ticket. It is very difficult to keep track of bugs when they are not in their own tickets, and it is easier for you to make multiple tickets than for the mods to separate them.