Path of the Dragon Slayer

Through massive amount of combat and physical training you have mastered combat 

Posession

When you are in the possession state you gain +2 necrotic damage to your weapon attacks and can make a weapon attack on your bonus action.   After every turn you roll a DC 7 + half your barbarian level wisdom saving throw. if you fail you can use your reaction to forcefully exit rage and not attack your teammates but take one level of exhaustion.

Mindless Possession

Beginning at 6th level, you can’t be charmed or frightened while in Possession. If you are charmed or frightened when you enter your Possession, the effect is suspended for the duration of the rage. Additionally while you rage or are in possession you can wield a two handed weapon as a one handed without reducing the damage dice.

Mechanical Bombs

You gain proficiency in tinkerer's tools. you can use these to make plethora of bombs and contraptions. additionally you can use these bombs as a bonus action.
1. Shrapnel Bomb- Target must make a DC 10 + half your barbarian level Dexterity Saving Throw or take 1d6 piercing damage. 
2. Stun Bomb - Target must make a DC 10 + half your barbarian level constitution saving throw or become stunned until your next turn this effect can only affect a target once per 12 hour period.
3. Smoke bomb - make a veil of smoke appear obscuring your image increasing your AC by +1 this effect persists until the end of your next turn
4. Poison bomb - Target must make a DC 10 + half your barbarian level Constitution Saving Throw or become poisoned taking 1d4 until they pass the constitution saving throw.
Material requirements
1 impact casing  
1 10th of a pound of gunpowder 
1 10th of a filler material. Shrapnel (Metal Scrap) Stun (Thunderpowder) Smoke (Sugar, and Potassium Nitrate) Poison (poison herbs, sugar, potassium Nitrate) 

Demonic Grasp

Starting at 14th level, when you take damage from a creature that is within 5 feet of you, you can use your reaction to make a melee weapon attack, or throw a bomb at that creature. you also gain advantage on death saving throws but once you stabilize you gain 1 level of exhaustion.