Hey , thanks for the information. I ended up using Hierarchical Instanced Static Mesh to create instances with collision. This appears to work extremely fast. I’ve split my terrain into two parts, one is a gigantic single mesh with no collision, and the other the same mesh broken into regions (components). These components do have collision(static) but I’ve turned the visibility off after they are built. This appears to retain the collision while hiding the actual mesh. Now that I’m updating parts by removing them from the terrain RMC system and making an instance in the HISMC I need to update the collision of the RMC that is collision slices with visibility turned off. I thought it would automatically update the collision because I’ve updated the vertex locations of that RMC slice. Does it matter that the RMC visibility is turned off? I still want the collision to work, but have the visibilty to be turned off. Any ideas?