Circle of Iron (5e Subclass)
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Circle of Iron
Most druids are purists that believe that they may only protect themselves with the "gifts of nature". Hides and leathers, furs and scales. The druids' desire to wield only these crude implements is nothing more than a disservice to their incredible abilities. Druids of this circle believe that metal is not only a natural device worthy of use by a druid, but that metal is the greatest of gifts that mother nature has provided her children.
(As a worldbuilding note, this circle might be particularly interesting as a dwarf-centric druidic circle.)
Starting at 2nd level, you shed your superstitions towards the use of metal armor and weapons. You may now wield armor and weapons made from metal and suffer no penalties for doing so. You also gain proficiency with all simple weapons and martial weapons.
Also starting at 2nd level, you gain the ability to harden your resolve, much like tempering steel. As a bonus action, you may grant yourself temporary hit points equal to your Druid level. These temporary hit points are lost at the beginning of your next turn. You may use this feature a number of times equal to your Wisdom modifier. (Minimum 1) You regain all uses of this feature when you complete a long rest.
Starting at 6th level, your attunement to the natural power of iron empower's your Wild Shape. While in your Wild Shape, your armor class is increased to 16 if the beast you transformed into has a lower armor class than this. In addition, when you Wild Shape, you may expend a spell slot to gain temporary hit points equal to 5 * the spell slot's level while wild shaped. For example, if you transformed into a wolf, you could choose to expend a 3rd level spell slot as a part of your Wild Shape and gain 15 temporary hit points on top of the wolf's normal hit points.
Might of Steel
At 10th level, you have become resilient as steel, refusing to buckle under constant punishment. If you are reduced to 0 hit points, but not killed outright, you are instead reduced to 1 hit point and gain the benefits of your "Iron Will" feature, without expending a use of your "Iron Will". You may use this feature once and regain use of this feature upon completion of a long rest.
Starting at 14th level, you have become one with the earth, embodying the resilience and power of iron. You are permanently under the effects of the spell "Barkskin", as your flesh has hardened like iron. You also gain the ability to cast "Stoneskin" without expending a spell slot or material components. While casting "Stoneskin" in this way, you do not need to maintain concentration on the spell. You may cast "Stoneskin" once in this way, regaining the ability to do so upon completion of a long rest.