I never understood what "war games" are
It is a training to test systems, soldiers/sailors and tactics.
So, as an example, for something like this they could have all the ships working as a unit advancing towards a target while maintaining a certain formation to see if they can do it without problems. Perhaps even with a submarine acts as an enemy trying to get close or they can also have drones fly toward them to simulate air attacks so that the ships can blow them up to see if everything works as it should.
All of that, and sometimes additionally as a show of force and/or provocation, or as a pretext for troop movements.
Don't US Wargames usually prove that basically their own guys would slaughter them something silly if OPFOR didn't have both their hands tied behind their backs for the purpose of the war game?
Thanks, comrade