Blindness Adaptation

You have permanently suffered the blind condition at some point in your past. Through extensive training you have adapted to that condition and gain the following benefits.

• You have blindsight out to a radius of 30 feet. If you are deafened your blindsight is reduced to a radius of 10 feet. If you are deafened and unable to smell you cannot use your blindsight at all.
• You can see invisible creatures within your blindsight range, unless the creature successfully hides from you.
• You have advantage on perception checks that involve hearing and smell.
• You are vulnerable to thunder damage and have disadvantage on constitution saving throws involving poisonous vapor and noxious fumes. Additionally if you fail a saving throw against effects that make a particularly loud noise (such as shatter or fireball) you are deafened until the end of your next turn.
• The DM may award this feat for free if the character is still afflicted with the blindness.