It would be nice if this was the other way round :'''''(

# this will ruin your day

endgame smash --service all --evil-principal ""

# This will show you how your day could have been ruined

endgame smash --service all --evil-principal "" --dry-run

Looks like it can be reversed with --undo, but brown trousers time if you groggily run it at 08:30am coffee in hand.