The Defenders Curse

Your years of training against the harshest attacks grant you the ability to block even the strongest blows. As an Action, you bolster your defense to the extreme, at the cost of your offensive capabilities. For the next minute, critical hits against you do not automatically hit, the attacker gains only half their usual attack bonus, and you cannot critically fail (rerolling all Nat 1's), but your movement speed is reduced by half, your attack modifier is halved, your Dex mod is reduced by 3, and you reroll all 20's on attack rolls. In addition, you may use your Constitution save in place of Dex saves. You may use this ability a number of times per day equal to your Constitution Modifier plus your Wisdom Modifier (Minimum of 1).