Path of the Construct

When you rage your form actually begins to shift and change. It resembles a golem of your choice in the upcoming selections. How this came to be is currently unknown, but it certainly comes from an unnatural ritual of some kind. When you pick this subclass at third level, choose a golem type. You may change your type once every time you gain a level in this class. When you change your golem type, all previous abilities become that of the currently chosen golem type.

Head of a Construct

Stone

Beginning at 3 level when you are raging you gain resistance to poison damage. Additionally, while raging, if you an enemy within 5 feet of you to casts a spell on you, you have advantage on any saving throw that it forces you to make.

Iron

Beginning at 3 level when you are raging, as a bonus action on your turn you may expel poisonous gas in a 15 foot cone from your body. Any creature caught in the cone must make a constitution saving throw Dc = 8+prof+con. On a failed save the creature takes 2d6 points of poision damage and half as much on a successful save. You may use this feature a number of times equal to your constitution modifier per rage.  The damage of this ability increases as you gain levels in this class. (3d6 at level 9,  4d6 at level 13, 5d6 at level 17)

Clay

Beginning at 3 level when you are raging if you take more than 10 damage from one creature in a round, you become enraged and deal an additional 1d8 points of damage to that creature on each attack but you have disadvantage on attack rolls against creatures other than the target of your enraged. If more than one creature meets this requirement you are enraged at all creatures who meet this requirement. This number increases by 1d8 at level 9, level 13, and level 17

Heart of a Construct

Stone

Beginning at 6 level while you are raging as an action you may cast the slow spell centered on yourself. The spell save dc is equal to 8 +prof + Con. Raging does not interfere with your ability to cast the spell or concentrate on the spell, though you must make concentration checks like normal. You regain the ability to cast this spell at the end of a short rest or long rest.

Iron

Beginning at 6 level, you gain resistance to fire damage while raging. And if you take fire damage, the first melee attack on your next turn deals additional fire damage equal to ½ the fire damage you took.

Clay

Beginning at 6 level, while raging you may use your action to cast haste on yourself. Raging does not interfere with your ability to cast this spell or concentrate on it. Though you must make concentration checks like normal. You regain your ability to cast the spell at the end of a short or long rest

Immutable Form

Beginning at 10th level, while you are raging you are immune to charmed and fear effects. Additionally you are immune to any effect that would change your form and you are immune to petrification

Body of a Construct

Stone

Beginning at 14 while raging you are immune to poison damage and after you cast the slow spell at the beginning of your turn roll a d6. On a roll of 5-6 you regain your ability to cast this spell.

Iron

Beginning at 14 level when you rage, you are now immune to fire damage, and the next melee attack deals fire damage equal to ½ of the fire damage you would have taken. Additionally you heal hit points equal to the amount of fire damage you deal with this melee attack.

Clay

Beginning at 14 level once per turn when you deal damage to a creature, it must make a constitution saving throw against a DC of 8 + prof + Con. On a failed save the creature has its maximum hit points reduced by ½ the amount of damage that it took.