Base Class: Barbarian
A Berserker makes their place in any battle, dying a thousand times and walking out alive, surviving wounds and attacks that would kill most only to come back the next day in search of their next fight. An insatiable desire for battle leads them to become fierce nigh-unkillable soldiers of war. A warning to all those who dare fight these arbiters of death, for their presence and will alone break even the most fearless of men...
Bloodlust
Starting when you choose this path at 3rd level, you can go into a bloodlust when you rage. While raging, you can choose to go into a frenzied killing spree disregarding all things except combat. You can make a single melee weapon attack as a bonus action on each of your turns as well as add +1 damage to all attack rolls and weapon damage. During this rampage your AC is lowered by -2.
At higher levels the damage will scale as follows; +3 at 10th level, +5 at 15th level, and +8 at 20th level.
Rip and Tear
Starting at 6th level, all forms of defense feel the effect of your onslaught. Whenever you successfully make two melee weapon attacks against the same creature on the same turn, the target receives a -1 penalty to their Armor Class. This penalty can stack, to a maximum penalty equal to half your proficiency bonus rounded down.
Fear Incarnate
Beginning at 10th level, you can use your action to frighten someone with your menacing presence. When you do so, choose any creature that you can see within 30 feet of you. If the creature can see or hear you, it must succeed on a Wisdom saving throw (DC equal to 8 + your proficiency bonus + your Strength modifier) or be frightened of you until the end of your next turn. This effect ends if the creature ends its turn out of line of sight or more than 60 feet away from you.
If the creature succeeds on its saving throw, you can’t use this feature on that creature again for 24 hours.
Retaliation
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 against that creature.