A particular attack in an enemy's arsenal which is significantly more dangerous than most of its attacks. If you have a party, it will almost always target all party members, and it often takes off the majority of your hit points, if not worse. It's a staple for That One Boss to have one of these, possibly more. This attack showing up even once is always bad news; if the AI Roulette gives you two in a row, expect to see the Game Over screen. Whether or not you can beat That One Boss that uses this attack usually depends entirely on whether or not you can avoid/endure/recover from it.