As a warforged, you are made to protect. A magical nanotechnology-esque shield is built inside your mechanics that you have now learned to manifest.

Once per Short Rest, you can use a Bonus Action to manifest your Warforged Nanoshield causing beads of metal to spread across your chest and reinforce your armor. The shield lasts for 1 minute. While it is active you gain a +2 bonus to your AC. You cannot be holding a shield when manifesting the Warforged Nanoshield.

As a Bonus Action, you can manipulate the shield to extend outward from your body 10 feet in any direction until the start of your next turn. Creatures behind the extended shield gain half cover, which gives them a +2 bonus to their AC and Dexterity saving throws. You can manipulate the shield in this way a number of times equal to your proficiency bonus. Additionally, when you extend the shield outwards, you sacrifice the AC bonus that you receive from this ability.

(You must be a Warforged to take this feat.)