I’m suffering with the same problem, couldn’t find any topic related to this issue either. If there are too many foliage instances in the game, removing foliage instances or any instance in the game causes FPS drops. For example, I’m using hierarchical instance mesh for my building system. If I build or remove a building part in the environment map which is full of foliages, it causes huge FPS drops even though I don’t touch foliage instances.