A Multicast Delegate in C# is a delegate that can hold references to multiple handler functions[1][2][3]. When the multicast delegate is invoked, it calls all the referenced methods in the order they were added to the delegate[1][4][5].
To create a multicast delegate, you first create two regular unicast delegates (delegates that reference a single method) and combine them using the + operator[4]. This internally calls Delegate.Combine with the two delegates as arguments and returns a new multicast delegate instance[4].
The behavior of a multicast delegate when invoked is as follows:
The methods that the delegate object points to are invoked in sequence in the order they were added to the delegate[4]
The return value of the delegate is the return value of the last method invoked - all the others are discarded[4]
