Unreal Engine Replication

Confirmation uncertain (Action may be rejected):

    Client (Instigator) calls UFUNCTION(Server, WithValidation) SomethingToHappenEverywhere();
    
    Server receives SomethingToHappenEverywhere() -> Role == ROLE_Authority ->
    
    Server verifies with SomethingToHappenEverywhere_Validate(); If true, continue
    
    Server calls UFUNCTION(Multicast) SomethingToHappenEverywhere_Multicast() and does the thing;
    
    All Clients receive SomethingToHappenEverywhere_Multicast(), verifies and does the thing.
    
    
Confirmation uncertain (Optimized):

    Client (Instigator) calls UFUNCTION(Server, WithValidation) SomethingToHappenEverywhere() and does the thing;
    
    Server receives SomethingToHappenEverywhere() -> Role == ROLE_Authority ->
    
    Server verifies with SomethingToHappenEverywhere_Validate(); If true, continue
    
    Server calls UFUNCTION(Multicast) SomethingToHappenEverywhere_Multicast() and does the thing;
    
    All Clients receive SomethingToHappenEverywhere_Multicast(), verifies and does the thing.
    
    
Confirmation certain (Action will always occur - cosmetic or not important):

    Client (Instigator) calls UFUNCTION(Server) SomethingToHappenEverywhere() and does the thing;
    
    Server receives SomethingToHappenEverywhere() -> Role == ROLE_Authority ->
    
    Server calls UFUNCTION(Multicast) SomethingToHappenEverywhere_Multicast() and does the thing;
    
    All Clients (Except the instigator) receive SomethingToHappenEverywhere_Multicast() and do the thing.