Druids of the Circle of the Monstrosity are unorthodox hunters of the unnatural.  They firmly believe that to hunt the unnatural you must understand the unnatural and become the unnatural, a fight fire with fire mentality. They infiltrate their foes' forces to strike from within. These hunters rarely ever meet with each other, preferring to work alone or hidden within a city, watching out, and only meet in the direst circumstances within the lairs of slain foes. 

Embrace the Metal

Because of the demanding difficulties and to better meld into society to hunt down the unnatural, starting from level 2 you can wear medium armor made from metal and can use shields made of metal.  You also gain proficiency with all simple and martial weapons and gain proficiency with the deception skill.   

Unnatural Hunter

When you choose this circle at 2nd level, you gain the ability to wildshape into a monstrosity that you have slain or helped slay before limited to your wildshape table.  
    Additionally, you can expend a use of your Wildshape as a bonus action to morph your body and gain one ability (Trait, Action, Reaction but not the Multiattack action) from a creature you can transform into via Wild Shape while maintaining your own form. The morph will suit your current body size and shape and apply similar limitation with DM discretion.

Few examples may include:

• Morph your head into a Wolf head to gain either the bite action or the keen hearing and smelling trait but not both, limitation you cant speak or cast spells that contain V component.
• Morph your back and grow wings from Giant eagle gain Fly speed equal to the giant eagle flying speed, limitation is that your armor must be modified to accommodate your wings and you must be at least level 8.
• Morph your inner body to gain temp hit points equal to half the hit points of any creature you can change into or to gain one resistance or one immunity damage type that the creature has.
• Morph your Brain to gain a creature skills and learn its language.

Circle Spells

Your mystical training in hunting the unnatural expands your spell library, infusing you with the ability to cast certain spells. At 3rd, 5th, 7th, and 9th level you gain access to circle spells.  Once you gain access to a circle spell, you always have it prepared, and it doesn’t count against the number of spells you can prepare each day. If you gain access to a spell that doesn’t appear on the druid spell list, the spell is nonetheless a druid spell for you.  

Once you gain access to a circle spell, you always have it prepared, and it doesn’t count against the number of spells you can prepare each day. If you gain access to a spell that doesn’t appear on the druid spell list, the spell is nonetheless a druid spell for you.

Druid Level	Spells
3rd	alter self, see invisibility
5th	counterspell, vampiric touch
7th	dimension door, locate creature
9th	greater restoration, hold monster

Extra attack

Starting at 6th level you can attack twice instead of once whenever you take the Attack action on your turn. 

Monstrosity Empowered

Starting at 10th level, you can use your Unnatural Hunter ability to gain two abilities at the same time from the same creature or different creatures by expanding a use of Wild Shape for each Ability.  At 20th level you can use four abilities at once.  Additionally, you can use your Wild Shape to transform into a form with a CR as high as your druid level divided by 5, rounded down.  

Predator of the Dark

When you reach level 14 you can use your experience to instill fear in the hearts of your enemies. As an action, you can choose a number of creatures up to your Wisdom modifier (minimum of one creature) within 60 feet of you. Each target creature must make a Wisdom saving throw against your spell save DC or be frightened for one minute.  Aberration, constructs, monstrosity, oozes and undead have disadvantage on the saving throw.  A creature that is immune to the frightened condition is still subject to the effect but has advantage on the saving throw.  A creature that fails its save by 5 or more is paralyzed, unless it is immune to the frightened condition.  A creature can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success.  A creature that succeeds on its saving throw is immune to this ability for 1 hour.