I think you misunderstand me. Look at how Cities Skylines is handling water. A simple flat surface is not enough, the water has to appear to flood an area that’s below water level. Much like dynamic ripples created by the old FluidSurfaceActor and what Epic has demonstrated with Blueprint Render Targets, but that it should also raise the water level directly, as in the vertices moving up. And it does affect gameplay, that’s the point. We have to simulate at least somewhat realistically a flooding if a dam breaks (hence the Skylines reference)