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There was a trope when a military-like group in training session gets attacked and it becomes a real battle, but I forgot the name
We can never truly eradicate the coronavirus, but we can suppress its threat like influenza
@OP: That's covered by Let's Get Dangerous!
If you mean that it goes from being fun to being the sort of thing that breaks up friendships, that would be tropes like Berserk Button, Trauma Button, and Dude, Not Funny!.
See also UsefulNotes.Trigger for the real-world concept in psychology, which are not something to joke about.
Edited by Scorpion451
Thanks
4tell0life4 is thinking of Things Get Real
Edited by molokai198
A group of people are pretending (Acting, roleplaying, etc) until someone brings up a very personal theme and Shit gets real
Edited by Ivann