On number 2. I’m not 100% sure but when dealing with physics based animations such as wind it’s often common for it to never be 100% synched with every client. Reason is the game will send the physics data down to the client, but each clients GPU processes things differently in regards to physics. Trying to run physics simulations then passing the draw code down ends up costing a ton of bandwidth, so instead most engines run the simulations serverside, package up the physics simulation data and send it down to the client to deal with. From there it’s GPU independent on the results. It will be really close, but never 100%. Now with that said I haven’t got into if UE4 has made changes to how it’s dealing with the simulations, in regards to large scale. I know in some situations it’s key for “physics” to be synced, IE someone shooting a barrel and it’s position being exact on all clients, but that would still mostly come at a replication of position hit for data. If it’s not important though IE wind affecting tree movement or such with small variations, being acceptable most engines save the bandwidth, just send or cache the simulations and force client machines to deal with it.