Under Harm, it says that if you ever need to mark harm and have no boxes left, you die.

Under Harm, it says that if you ever need to mark harm and have no boxes left, you die. So, if a character had taken (after applying reduction from armor) 3 harm from one attack, then 2 more harm from another attack, that’s all 5 boxes filled exactly. So do they die instantly, or would they need to take a 6th point of harm. (Or wait until the MC decides it’s appropriate to “worsen” their wounds and effectively take 1 more harm as a result.)

Basically, does harm have to “overflow” your boxes to kill you outright, or does the 5th do it instantly?