Almost finished with blueprintable ECS plugin for UE4
Sample demo has 10000 entities flying around changing 2 animations.
It would be useful for plants rees that can grow, vehicle traffic or fishes.
Or bullets if you really want a bullet hell.
Only static meshes so far, since render system uses HISM as an output.
But I’m thinking about regular actors too if you don’t go too crazy on numbers performance should be decent.