Path of the Forge

Barbarians who follow the Path of the Forge are able to channel power from the Elemental Plane of Fire into their rage. They use their knowledge of the forge to bolster their weapons and armor while improving the weapons of their allies. 

They are typically incredibly skilled Blacksmiths who continue to perfect their craft over time, utilizing the fire energy within to defend others from danger.

One with Flame

Starting at 3rd level, you have become used to the fires of the forge and the strength it takes to harness them. Your body glows with the fires of a burning forge when you are raging. 

While raging, you gain resistance to fire damage and you don’t suffer the effects of extreme heat, as described in the Dungeon Master’s Guide and your weapon's damage type becomes fire damage.

If you have access to a source of fire, you may use a bonus action to touch them to the flame and superheat any metal-tipped weapons you are wielding. Doing so double your rage damage bonus for the weapon and changes the damage type to fire. Superheating a weapon in this way lasts until your rage ends, after which it returns to normal.

Forge Specialist

Starting at Level 3 you begin to hone and specialize your forge abilities beyond those of weapons and armor. Pick one forging speciality of those available below:

In addition to the benefits below, at the end of a long rest, provided you have a source of flame, you are able to create the necessary tools. 

Coinsmith - Your observation of coins and ability to smelt them leaves a deep sense of history and how things are made. You gain proficiency with a Forgery Kit as as well advantage on History checks regarding currency or economical practices.

Locksmith - Creating the mechanisms required to accurately design Locks, you gain proficiency in Thieve's Tools as well as advantage on Investigation checks to study locks.

Jewelsmith - Your delicate crafting of jewelry has left you with an eye for detail. You gain proficiency with Jeweler's Tools as well as advantage on Sleight of Hand checks to delicately place or create items.

Coinsmith

Your observation of coins and ability to smelt them leaves a deep sense of history and how things are made. You gain proficiency with a Forgery Kit as as well advantage on History checks regarding currency or economical practices.

Jewelsmith

Your delicate crafting of jewelry has left you with an eye for detail. You gain proficiency with Jeweler's Tools as well as advantage on Sleight of Hand checks to delicately place or create items.

Locksmith

Creating the mechanisms required to accurately design Locks, you gain proficiency in Thieve's Tools as well as advantage on Investigation checks to discover the state of locks.

Friendly Fire

At 6th level, you learn how to more deeply channel your forge skills. 

Your resistance to fire damage now applies at all times. Additionally, your weapon's fire damage while superheated now ignores resistance to fire damage.

While raging, you can touch an object and channel the heat of your forge into it. If the object is not being worn or carried and is flammable, you touch it automatically and it is set on fire. If it is being worn or carried, make a grapple attack against the bearer. On a success, the bearer is grappled, takes 2d8 fire damage. when the creature takes this damage, it must succeed on a Constitution saving throw equal to your unarmored AC or drop the object if it can. If it doesn't drop the object, it has disadvantage on attack rolls and ability checks until the start of your next turn. As long as you have the creature grappled, you can use a bonus action to cause this damage again.

Superheated Rage

Starting at Level 10, your weapons are automatically superheated as part of the Rage bonus action. 

Quenched Blade

At level 10, you are better able to control entering and exiting your rage. A quenched blade always comes back stronger. 

Dropping your rage(no action) emits a blast of steam that pushes all medium or smaller creatures next to you back 10 feet if they fail a strength saving throw DC equals 8 + proficiency + Constitution.

Additionally, after using this ability until you exit initiative, you are resistant to cold damage as well as fire damage.

Master Forger

Your time as a forger has made you into a heartier, tougher material. 

You are now immune to fire damage at all times.

Your armor and weapons are immune to the spell Heat Metal.

Additionally, you have learned to hone weapons and armor to a fine edge in the fires of your forge. As part of a long rest, you can spend an hour smithing a magical or non-magical weapon to grant it a +1 bonus to attack and damage rolls, or a piece of armor to grant it a +1 bonus to AC. The effect lasts for a number of days equal to your proficiency bonus, and you can only smith one item per long rest.

In Addition, the cost and time to construct a stronghold are cut in half for you.