Path of Symbiosis (Interplanar Ooze)

While most Barbarians choose their path, some are chosen. You are infected with a symbiotic entity. A creature alien to this world, perhaps? A Demonic presence from the abyss? Weakened remnant of an Illithid Tadpole, maybe… Whatever the origin, there is a new voice inside your head, and it seems to like its new home. It has bonded with you, for better or worse.

Some hosts strike a deal with their new being, while others are subjected to the whims of the aberration. The symbiotic entity itself could have any number of goals. To find a new home. Devour new worlds. To herald its kind to your world. Or other, more sinister plans...

Altered Rage

The Interplanetary Ooze, once you let it envelop your body, grants you many great benefits and abilities.

You gain Darkvision, or, if you already have Darkvision, it now extends and extra thirty feet.

Your rage is no longer some simple yet intense mental state. Now it becomes a literal physical change, imbuing your body with an extra layer of gooey skin.  Your new rage form creates natural weapons for use in combat as well. While Raging, you now have a Claw and Bite attack.

Claw and Bite attacks have a reach of 5ft On a successful hit of these attacks, roll 1d6 + STR for damage. 

If you kill a creature with a fatal Bite attack, your Symbiotic Being devours a piece of your opponent, providing sustencance to the both of you. You may roll equal to your damage die amount and regain health points equal to the number rolled.

All attacks count as magical. You may use a Claw or Bite attack as a Bonus action. 

The Interplanar Ooze also grants you two spell abilities: Disguise Self and Mage Armor. You may only cast either of these abilities once per short rest. 

Otherworldly Empowerment

Your Altered Rage form advances at Level 6 as your bond with the Interplanar Ooze deepens.

The viscous ooze now forms tiny vestigial tendrils that lift away from the surface of your combined skin. They wiggle about in all directions.

Tendril - You attack with your newly formed Tendrils in addition to Claw and Bite attacks. Tendril attacks have a range of 10 ft. and are considered magical. You may Grapple your opponent on a Critical Hit made with these tendrils.

 

Strengthened Bond

At 10th level, you and your Interplanar Ooze have become inseparable, in both a literal and figurative sense. Once you obtain tenth level in this subclass, you cannot rid yourself of this being by normal means. The pair of you are now bonded, forever.

On the plus side, You cannot be surprised, you have advantage on saving throws involving psychological effects such as Fear, Horror, Charmed, etc., and Rage no longer breaks concentration for spells, now that you have two minds working as one. 

You also gain the Viscous Outburst ability that you can use once per long rest.

Your Altered Rage form evolves one step further as well.The Tendril appendages now grow longer and whip around you in all directions. Your Oozy companion can also make an emblem or coat of arms appear on your chest (Spider, Skull, Fireball, etc.) If you so choose to have one.

Symbiotic Flight

At 14th level,  your Interplanar Ooze grants you the ability to Fly for a short period.

Your Altered Rage form becomes enhanced one final time.Your mass is now thicker and ropey. You have less tendrils overall, but they seem tougher and sharper than they were before.

You may grow apair of batlike, sinewy wings sprout forth from your back. You have a fly speed of 40 feet for one hour in your Altered Rage state.

Your Claw, Bite, and Tendril attacks roll for 4d6 + STR. 

Mindless Rage

The two of you can also now enter a heightened battle state as well. While raging and below half of your health, your two minds become one, entering a Primal mental state neither of you can break from until you lose your rage or are brought to 0 hp. Your attacks can roll an extra 1d6 for damage. However, discerning friend from foe becomes much more difficult. If one or more allies are within five feet of you when you choose to attack as your action in this state, roll 1d6. An even number allows you to hit your intended target. An odd number forces you to attack one or more of your allies at random.