You can sometimes defiantly shrug off spells and attacks that would kill a lesser creature.
Prerequisites
Benefit
Once per day, after you roll a natural 1 on a saving throw or a critical hit is confirmed against you, you can either reroll that saving throw, or force the creature that confirmed the critical hit against you to reroll the critical confirmation roll. This does not stack with other effects that allow you to reroll a saving throw or force an opponent to reroll a critical confirmation roll. You may only make one reroll.