In this tutorial, I go into depth about how Multiplayer Replication works. I cover topics like the difference between the various Multiplayer Events; Run On Server, Multicast, and Rep Notify. I also go on a few tangents like how to optimize your code by disabling "Tick by default" and why you should Avoid Casting whenever you can. It's a long video, but I think it will be worth your time as it is a unique way to learn how to code Multiplayer with Blueprints.