Through a life time of war you have become mentally scarred by it, disadvantage on wisdom and intelligence saves due to having a scarred mind but advantage on skill checks related to war, upon hearing a sound related to your war eg. For steampunk explosions and gun shots, roll a d6 on a 1 you go into fight or flight if below or athalf hp use your reaction to dash and move your dashed movement speed the opposite direction of the noise (avoiding obvious dangers) or if above half hp use your reaction to strike the nearest creature, you will also be recognized as a veteran on sight