This is primarily used for the King Objective. Very simple to setup. Simply add an AOCAssassination Objective from the Actor Menu in the Generic Browser.
Give it the following settings. Make sure to also assign it to an AOCPlayerStart set to EFAC_None
Here is the Kismet. Again, very simple compared to other objectives.
The Objective will end when the King is killed. This is a remote event that only needs an output.