Path of the Fallen

Some barbarians are fueled into rage by their own passions, or take inspiration from animals in nature to empower their martial prowess. Those who tread upon the Path of the Fallen are different, however, having been touched by the influence of the Lower Planes at one point in their lives. Whether gifted power by a scheming archdevil or having drunk the blood of a felled demon, these barbarians walk a fine line between restraint and unholy wrath, the forms they take on during their rage frightening to the everyday witness.

Fiendish Visage

Starting when you choose this path at 3rd level, your fiendish connection grants you the ability to cast the thaumaturgy cantrip at will. As well, you gain the ability to speak either Abyssal or Infernal, depending on the source of your fiendish strength. When you rage, you can choose to manifest one otherworldly trait, as detailed below. When you reach 6th, 10th, and 14th level in this class, you may additionally choose to manifest two, three, or all these traits.

Horns. As a bonus action on your turn, you can attempt to ram a target with your horns. Make a contested Athletics check with the target of your choice. On a success, you knock your target prone.

Fangs. As an action on your turn, you can attempt to bite a target within 5 feet of yourself. Make an attack roll using your Strength modifier + your proficiency bonus. On a successful hit, your target takes 1d8 + your Strength modifier in piercing damage, and must succeed on a Constitution saving throw (DC 8+ your proficiency bonus + your Constitution modifier) or be poisoned until your rage ends. At the end of each turn, the target can roll another saving throw to attempt to resist the poison's effect.

Claws. You gain a climbing speed equal to your walking speed. As a bonus action on your turn, you can attempt to grapple a target within range. Make a contested Athletics check with the target of your choice. On a success, your target is now grappled.

Hooves. Your speed increases by 10 feet, and your jump distance is tripled while you are raging.

Tail. Your tail is prehensile, allowing you to wield an additional light weapon and attack with it as a bonus action, adding your Strength or Dexterity modifier to the damage roll. Due to your tail's length, you have reach with this chosen weapon.

Wings. Starting at 6th level, you can sprout a pair of fiendish wings from your back, gaining a flying speed equal to your current speed. You can't be wearing heavy armor to gain these benefits.

Diabolic Vigor

Beginning at 6th level, you are immune to poison damage and the poisoned condition while raging. When you gain this feature, choose acid, cold, fire, or lightning. You gain resistance to this damage type while raging, and can replace any damage you deal with the Fiendish Visage trait with your chosen damage type.

Elemental Fury

Beginning at 10th level, as part of an attack or your reaction, you can target a creature within 10 feet of you to be struck with elemental energy. The creature must succeed on a Dexterity saving throw (DC 8 + your proficiency bonus + your Constitution modifier) or take 2d10 elemental damage, determined by the type you chose in the Diabolic Vigor feature. They take half as much damage on a success. You can use this feature a number of times equal to your proficiency modifier, and regain all uses when you finish a long rest.

Alternatively, you can expend two uses of Elemental Fury to amass additional energy by exhaling or beating your wings, taking an action to do so. Each creature in a 20-foot cone must succeed on a Dexterity saving throw (DC 8 + your proficiency bonus + your Constitution modifier) or take 4d10 elemental damage, determined by the type you chose in the Diabolical Vigor feature. On a successful save, the damage is halved. 

Unholy Might

Starting at 14th level, you have advantage on saving throws against spells and other magical effects while raging. If your Relentless Rage feature is triggered successfully, you can use your reaction to deal 5d10 elemental damage, determined by the type you chose in the Diabolical Vigor feature, to the target that reduced you to 0 hit points, so long as they are within 60 feet of you. Once Relentless Rage fails, you cannot use this part of Unholy Might until you finish a long rest.