Path of the Spirit Blaster

A select few barbarians take the phrase, "explosive temper", a bit too literally. They've learned to unleash their rage in explosive blasts, instead of prolonged and simple blood thirst. The Path of the Blaster is filled with destruction, sacrificing endurance for power in its purest form. First taught to mortals by the Yokai, the blaster uses the energy of emotion and destruction itself to fuel its fury.

Discipline of Destruction

When you choose this path at 3rd level, you adopt a discipline that determines how you manipulate your blasts. These were taught to the first mortals by the yokai, in order to maintain their control over the mortal plane, but they were adapted to suit the needs of the Blaster. 

• Discipline of Control
• Discipline of Power
• Discipline of Change

At 15th level you can choose an additional discipline.

Rage-Induced Blasts

At 3rd level, you can no longer use your rage as normal. Instead, as an action you can release a furious blast of energy by expending a use of your rage. When you gain this feature, you can choose for the blast to deal either fire or lightning damage, and you can spend a short rest to change it to either fire or lightning. The DC for the blast is 8 + your constitution modifier + your proficiency bonus. All blasts originate from your hand, which cannot be holding anything.

The type of blast is determined by your discipline.

• Control - When the blast is triggered, you gain a pool of d6s used to direct your blast. The number of dice in this pool equals 5 + your level. Each die manifests as a 5 by 5ft cube of explosion that you can arrange as you wish. Each cube must have at least one face adjacent to the face of another cube, and must be connected to you. You can overlay the cubes up to 4 times (4d6). Each creature in the area must make a Dexterity saving throw. On a failed save, the creature takes as much damage equal to the amount of dice overlapping it, or half as much on a successful save.
• Power - When the blast is triggered, it fires energy away from you in a 30 ft. cube in a direction of your choice, targeting all creatures and objects in the area. Each creature in the area must make a Dexterity saving throw, on a failed save taking 3d6 damage and get pushed away a number of feet equal to 5 * your proficiency bonus, and on a successful save take half damage and aren't pushed. Objects in the area take double damage. The damage of this blast increases by 3d6 when you reach 6th level (6d6), 10th level (9d6), and 14th level (12d6).
• Change - When the blast is triggered, you can change the damage type to thunder, psychic, or necrotic. All creatures in a 30 ft. cone extending from you must make a Dexterity, Constitution, or Intelligence saving throw (your choice), taking 2d6 damage on a failed save or half as much on a successful one. For the next minute your melee weapon attacks deal the same type of damage as your blast. The damage of this blast increases by 2d6 when you reach 6th level (4d6), 10th level (6d6), and 14th level (8d6).

Doing this is tremendously stressful on the body, after using the blast, you have vulnerability to all damage until the start of your next turn.

Soul of the Yokai

Starting at 6th level, your connection to the Yokai manifests itself in strange ways, and lets you draw upon some of their supernatural aspects. You can choose to have tiny intangible spirits float around you, taking the form of any creature you want, but whatever form they take, they are clearly harmless and fake. They lack the ability to interact with anything. You also learn the Thaumaturgy cantrip.

Spirit World Connection

When you aren't unleashing explosive fury upon your enemies, you can reach calm states unheard of for most barbarians, due to your connection to the Yokai. After a short rest, you gain the following features,

• You can turn one of your limbs ethereal/intangible, ignoring all objects and effects that aren't on the ethereal plane, allowing your limb to move through objects on your original plane. Your limb is still visible from the normal plane however, though it is translucent.
• You can see 15 ft. into the ethereal plane, but everything appears in shades of black and white.
• You can get simple messages across to undead and fiends (anything that can be considered a spirit) even if you don't share a language.

You also gain an additional feature based on your discipline,

• Control - As an action, you can touch one object that isn't being worn or carried, and is no larger than 4 feet in any dimension, to become magically fixed in place for up to 10 minutes. This requires your concentration (as if concentrating on a spell). The object won't move, even if it's defying gravity, and can hold weight up to your carrying complicity. More weight will cause the object to fail and return to normal. A creature can use an action to make a Strength check against your blast DC, moving it up to 10 feet on a success.
• Power - You can destroy matter within 1 foot cube by spending a minute in constant contact with a non-magical object. This cannot destroy lead, mythril, or adamantium, and destroyed objects turn into dust.
• Change - You can cast the disguise self spell at will.

Spirit Bombs

At 14th level you are able to manipulate your rage-induced blast even further, getting new offensive and defensive capabilities.

• Control - As a reaction when you are in the area of an instantaneous aoe attack from a creature that you can see, you can expend a use of your rage to reduce the damage it deals to every creature in the area by rolling however many d6s are in your blast pool.
• Power - When you trigger your rage-induced blast, you can sacrifice up to 20 of your hitpoints to increase the damage output by an equal amount, alternatively you can also increase the size of the blast, every 5 hitpoints increasing the size of the cube by 5 ft. (you can combine the effects). After doing so, you must succeed on a DC 18 Constitution saving throw or suffer 1 level of exhaustion.
• Change - After your rage-induced blast, you can choose 1 of the creatures that failed the saving throw. They gain vulnerability to the damage type of the blast for 1 minute, repeating the saving throw at the end of each of their turns.