The old WW2 Call of Duty games had some great anti-war levels, you should take inspiration from that.
In terms of unfairness, I’d say don’t worry much about it.
I’ve heard that the only way to accurately portray war in cinema, it’d be for bullets to randomly come out of the screen, killing audience members.
So yeah, no realistic way to be that unfair…
Anything you do, it’s fine. Intention is what counts! Don’t worry for people eventually enjoying the unenjoyable, its art after all!