Path of the Passenger

Some barbarians look to the skies for a higher purpose, and a lucky few have their wishes answered. Though the origins of their powers are shrouded in mystery, these barbarians walk the Path of the Passenger, carrying inside of them a shard of extraterrestrial might. The bond to their shard strengthens as the barbarian's prowess grows, tying them together in a symbiotic relationship.

These extraterrestrially gifted barbarians often join groups of extraordinarily skilled or brutal fighters, honing their newfound abilities by tempering themselves with battle. A scant few create their own groups, attracting into their midst other uniquely gifted folk, determined to devote their lives to exploring the dark mysteries of the multiverse.

Alien Physiology

Starting when you choose this path at 3rd level, your passenger bonds with your flesh and increases your healing factor beyond your species' limits. While you're raging, you may use your bonus action to heal 1d4 + your CON modifier hitpoints once every combat.

The dice increase to 2d4 at level 6, 3d4 at level 9, 4d4 at level 12, 5d4 at level 15, and 6d4 at level 18.

Ferrodermis

At 3rd level, your xenofuria rapidly transforms your skin into metallic plates during combat. While you're raging, you add half of your STR score rounded down to your Armor Class.

This increases to 3/4 of your total STR score rounded down at 14th level.

Pyrogenesis

Starting at 6th level, your passenger pushes you beyond your species' limits more drastically. You gain resistance to fire damage, and your attacks are enchanced with raging flames. Your attacks deal an extra 1d6 fire damage while you're raging.

This damage increases to 2d6 at level 11,  3d6 at level 14, and 4d6 at level 17.

Brutal Resonance

At 10th level, your body is a font of alien influence, and you know how to wield it. When you go into a rage, choose up to 5 other creatures of your choice within 60 feet of you. Until your rage ends, they heal 1d4 + your CON modifier hitpoints every time you deal at least 4 times your STR modifier in damage during your turn.

Once you use this feature, you can’t use it again until you finish a long rest.

Leviathan Awakening

Beginning at 14th level, your symbiosis with your passenger achieves its full potential, making you more dangerous the longer you fight. When you go into a rage, you start to transform. You must make an attack roll or take damage during each round to continue transforming. You revert one stage every round you don't attack or take damage.

If you're fighting within a space that is too small to let you grow in size, you'll remain at your current size category until you're in a space that can accommodate a larger size category. You still gain additional attributes.

Whenever you're no longer raging, it takes you 1 round per stage to fully revert to your normal form.

• Round 1: Your pyrokinesis grows stronger, forcing enemies to take 1d6 fire damage when they hit you with melee attacks. If you've taken more than 40 damage at the end of the round, your Armor Class increases by 1.

• Round 2: Your size increases by one category, causing your attacks to deal 1d4 additional weapon damage.  If you've taken more than 40 damage at the end of the round, your Armor Class increases by 1.

• Round 3: Your chest burns as hot as a furnace, making you immune to fire damage. If you've taken more than 40 damage at the end of the round, your Armor Class increases by 1.

• Round 4: Metal plates with dark red flesh between them splay out from either side of your back, giving you a flying speed of 50 ft. Your size increases by one category, causing your attacks to deal 1d4 additional weapon damage. If you've taken more than 40 damage at the end of the round, your Armor Class increases by 1.

• Round 5: Your metal plates no longer yield to mortal attacks, giving you immunity to non-magical damage. If you've taken more than 40 damage at the end of the round, your Armor Class increases by 1.

• Round 6: Your final form is revealed. Your size increases by one category, causing your attacks to deal 1d4 additional weapon damage. You cannot be taken below 1 hitpoint by anything other than a critical hit. If you've taken more than 40 damage at the end of the round, your Armor Class increases by 1.