After looking around I noticed that there was no errata for the completely useless feat “Prone Shooter” from Ultimate Combat, so I decided to make one myself and see what people thought in terms of use and balance. After making the initial feat I got the idea for a few other feats to benefit for the prone combatant. So please tell me your opinion about them.
Prone Shooter
Prerequisite: Weapon Focus (crossbow or firearm), Base Attack Bonus +1,
Benefit: If you have been prone since the end of your last turn, you can make a single ranged attack with a crossbow or firearm as a full-round action, gaining a +1 bonus on the attack roll. You gain an additional +1 on this bonus at base attack bonus +6, +11, +16, and +20 (for a maximum of +5 at base attack +20).
Special: You can combine the full-round action attack this feat allows with the benefit of Vital Strike, Improved Vital Strike, or Greater Vital Strike.
Prone Defense
Prerequisites: Dex 13, Dodge
If you have been prone since the end of your last turn, you gain an additional +2 bonus to AC against ranged attacks and the penalty to your AC against melee attacks is reduced by -2. A condition that makes you lose your Dexterity bonus to AC also makes you lose the benefits of this feat.
Normal: A prone character gains a +4 bonus to AC against ranged attacks and a -4 penalty to AC against melee attacks.
Lay Still
Prerequisite: Stealth 2 ranks, Survival 2 ranks
Benefit: If you have been prone since the end of your last turn, you gain a +2 circumstance bonus to Stealth. If you are gaining the benefit of cover while prone the bonus to Armor Class and Reflex Saves both increases by +2. If you are gaining the benefit of concealment while prone the chance of missing increases by 10%.
Dead Man Shooting
Prerequisite: Prone Shooter, Weapon Focus (crossbow or firearm), Base Attack Bonus +6
Benefit: If you have been prone since the end of your last turn, you can make a single ranged attack with a crossbow or firearm as a full-round action, gaining a +2 bonus on the damage roll. You gain an additional +2 on this bonus at base attack bonus +11, +16, and +20 (for a maximum of +8 at base attack +20).
Special: You can combine the full-round action attack this feat allows with the benefit of Vital Strike, Improved Vital Strike, or Greater Vital Strike.