Path of the Iron Heart

Catalyst Ideas
d6	Catalyst Source
1	A golem's heart
2	A symbiotic living construct
3	A gear or cog from the plane of Mechanus
4	A rare gnomish relic
5	A clockwork engine
6	An experimental duergar machine

Internal Storage

Starting at 3rd level, your semi-construct nature allows you to store essential objects for easy access. You have a compartment within your body 1 cubic foot in size. You can remove an object or insert one into this compartment as a bonus action on your turn.

Living Alloy

At 3rd level when you adopt this path, your catalyst uses your excess energy to improve your body and coat it in a regenerative layer. While you're raging, you gain a protective barrier. The barrier has hit points equal to half your barbarian level + your Constitution modifier. Whenever you take damage, the barrier takes the damage instead. If this damage reduces the barrier to 0 hit points, you take any remaining damage. The barrier can't absorb damage while it has 0 hit points, and regains any lost hit points at the start of each of your turns.   Additionally, at the start of each of your turns while you're raging, you can choose one of the following options. Until the start of your next turn, you gain its benefits.
Exoskeleton. You count as one size larger when determining your carrying capacity and the weight you can push, drag, or lift.
Independent Targeting. You have advantage on Wisdom (Perception) checks.
Propulsion. Your jump distance is doubled.

Kinetic Repulsion

Starting at 6th level, immediately after a creature hits you with a melee weapon attack while you're raging, you can use your reaction to redirect that energy back on the creature in the form of a concussive wave of force. The creature must succeed on a Strength saving throw (DC equal to 8 + your proficiency bonus + your Constitution modifier) or be pushed a number of feet away from you equal to the attacks damage roll. You can only use this ability once per rage.

Adaptive Shielding

At 10th level, your barrier gains resistance to one of the following damage types: acid, cold, fire, lightning, or thunder (your choice). You can change the resistance to a different damage type at the end of a long rest, choosing from the same options. If damage of the same type as your barrier's resistance would reduce it to 0 hit points, you gain resistance to any of the remaining damage.

Overdrive

Beginning at 14th level, you can push your catalyst beyond its limit, for a price. When you enter your rage, you can have your catalyst go into overdrive. When you rage in this way, and at the start of each of your turns until your rage ends, your current and maximum hit points are reduced by an amount equal to half your Barbarian level. This reduction lasts until you complete a long rest, and if this effect reduces your hit point maximum to 0, you die. Additionally, you gain the following benefits:

• Your barrier's hit point maximum is doubled, and you gain access to all options from your Living Alloy feature.
• Your walking speed is doubled.
• When you hit a creature with a melee weapon attack, you deal an extra 1d12 damage of the weapon's type.