Path of The Nano-Machines

All barbarians are somewhat brutal. Their rage grants them superior strength, durability, and speed. Barbarians who follow the Path of the Nano-Machines learn to transform that rage into an incredible balance of defense and offense, which manifests as metallic black coating on their body. When in a fury, a barbarian of this path taps into the forces of overwhelming brutality to come out of combat unscathed and an absolute victor.

Barbarians of this path are typically elite champions who fight for a country or group of people. They are the strongest battalion of their team, and a one man army. A phrase commonly associated with these barbarians reign true, "Don't **** with this warrior."

Rage Hardening

3rd-level Path of The Nano-Machines feature

While you are raging, you add your rage damage bonus to your Armor Class.

Hardened Strike

3rd-level Path of The Nano-Machines feature

 When you hit with an Unarmed Strike, you can choose to add 1d4 extra Force damage. If you choose to deal this damage, You can also force the target to make a Strength saving throw (DC equals 8 + Your Proficiency Bonus + Your Strength Modifier), being launched 10 feet away from you on a failure.

The damage dice increases as you gain levels in this class, becoming 1d6 at 9th level, and 1d8 at 16th level.

You can do this a number of times equal to your Strength modifier, before needing to take a short rest to do it again.

Responsive Defenses

6th-level Path of The Nano-Machines feature

When you enter a rage, you're given resistance to the first damage type that harms you. If you already have resistance to that damage type, then this effect ignores that instance and waits until a non resisted damage type harms you. This effect lasts until your rage ends.

Repairing Energy

10th-level Path of The Nano-Machines feature

While you are currently in a rage, you can use a bonus action to regain a number of hitpoints equal to your total number of Barbarian class levels. Any hit points that exceed your maximum are turned into temporary hit points. These temporary hit points disappear when your rage ends.

You can do this a number of times equal to your proficiency bonus, before needing to take a long rest to do so again.

Killing Blow

14th-level Path of The Nano-Machines feature

While you are raging, you can attempt a Killing Blow. You can forgo one of your attacks, and gain a -5 penalty to hit, to add an amount of d8 force damage roll equal to the amount of Hit Points you're away from your maximum divided by 10 (rounded down). You cannot use Reckless Attack on this ability. If you miss, then the target has advantage to hit you until the end of your next turn.

If this attack downs the target, they are instantly killed and cannot be revived by anything short of a wish spell. Once you use this ability, your rage immediately ends.