Base Class: Barbarian
The Sin of Wrath draws their power from the Abyssal taint of their own blood, allowing it to drive them into a frenzy feared by mortals and fiends alike.
Assault Mode
Starting when you choose this path at 3rd level, demonic power flows through you when you enter your rage. While you’re raging, you gain the following benefits:
You can add your rage damage bonus to your melee attack rolls using Strength.
Your movement speed increases by 15 ft and creatures have disadvantage on opportunity attacks against you.
You gain resistance to fire and necrotic damage.
The first time on each of your turns you hit a creature with a melee weapon attack, that creature takes an additional 1d6 damage of the weapon's type. This increases to 2d6 at 10th level, and 3d6 at 16th level.
Expertise
When you first select this subclass at 3rd level, you gain proficiency with brewer's supplies, and you can add double your proficiency modifier to your attack rolls with shortswords.
Full Counter
Beginning at 6th level, you learn how to counter harmful magic. If you or another creature you can see within 5 feet of you is targeted by a harmful spell or magical effect, you can use your reaction to reduce that damage by 3d10. If this reduces the damage to 0, you can take control of the magic, sending it back towards the creature who sent it. Make an attack roll with your Strength against that creature. On a successful hit, the target takes the damage of their spell or magical effect, plus the result of your dice roll.
As your level in this class increases, the number of dice you can reduce the damage by changes to half your level (rounded down).
God Slayer
At 10th level, you gain the ability to unleash a thousand strikes in the blink of an eye. As an action, you can force creatures in a 60 ft cone to make a Dexterity saving throw. The DC for this is 8 + your proficiency bonus + your Constitution modifier. On a failed save, targets take 6d10 force damage. On a successful save, targets take half damage. You can use this feature a number of times equal to 1 + your Constitution modifier, and regain all expended uses after completing a long rest.
Revenge Counter
At 14th level, your control over your Counter ability has grown to pinpoint accuracy. Once per long rest, you can force all creatures within 60 ft of you to make a Constitution saving throw. On a failed save, targets take 14d12 force damage and are stunned until the end of your next turn. On a successful save, targets take half damage, and aren't stunned.