I was GMing an NWoD game, only mortals. The party was investigating some sort of monster linked to many severed limbs being found along a small town somewhere in Ireland and their owners missing. They hear about one old lady that had a china shop having heard some relevant rumor, so they went to investigate. The lady is unhelpful and as polite as a Ghestapo officer, so one of the players tries to intimidate her. Unfortunately he had nothing invested in either Intimidate or Manipulation. So he rolls a critical die (you get successes only on a result of 10 on a d10 and if you roll 1, bad things happen) and he gets a 1. And that's how bad things start. Phase One: The guy botches his Intimidation completely while I manage to Crit on the old lady's resistance to coercion. Since he threw some lovely insults and threatened to kill her, she gets a shotgun that was under her desk (ironicly enough put there for help on a later encounter.) Initiative is rolled. Phase Two: Everyone manages to get some lukewarm results on initiative. But the grandmother with the artificial hip manages to get first place in Initiative. Phase Three: The old lady shoots the thug that threatened her in the chest and against all odds drops his health to Aggravated (for mortals that means every second that passes the guy gets closer to death.) That also happened to the trained soldier that tried to put her in a headlock, but failed. I started going for called shots so that her dice pool will drop and she will just drop already. Nope. The knife nut that was throwing knives at her for three rounds, failing to connect even a single hit, gets his head pop like a baloon. The last living character, the only one not fit for combat runs away scared to death by murdergranny. As soon as she gets to the door, one last shot hits her in the back and there you have it, TPK. And that is my worst string of rolls! The intricate hunt for a supernatural cryptoid ended because of Marge Dooley, Geriatric Commando and later retconned as a former IRA member. We still joke about it with these guys when we see each other.