The Broken Circle

Druids of the Broken Circle have abandoned life, nature, and the Druidic Oath. Instead of receiving their powers as gifts from the spirits as thanks for serving and protecting nature, Broken Circle Druids take their power by force. They drain the land and the spirits of their essence, and in so doing, gain unimaginable power. This power comes at a great cost, however. For a Druid to break the Circle is an affront to the laws of the world. This power, though great, begins to rot the Druid from the inside. Eventually, they become hollow shells filled with dark and twisted power - a grievous wound on the land. 

Corrupted Power

Starting at 2nd level when you break from the Druidic Circles and abandon your oath to Nature, you have learned to pull great power from all sources, even yourself. You may rend some of your own life force to shape into additional power.

Whenever you roll a d20, you may sacrifice and roll one of your hit dice from your hit dice pool. You lose hit points equal to the number rolled, and then add that same number to the total of your d20 roll.

Additionally, druids of the Broken Circle have gone so far against tradition that they may wear armor and wield weapons made of metal.

Twisted Form

A Druid who’s broken from the Circle is an affront to Nature. Starting at 3rd level, when you take the form of a creature with Wildshape, the beast is mutated, disfigured, and grotesque. When the Wildshape form ends for any reason, the creature’s body bloats and explodes with bile, puss, and other sepsis.

You are reborn from the gore in your normal form. Creatures within a 10 foot radius of you must make a Constitution saving throw against your spell DC, taking acid damage equal to your Druid level on a fail and half on a success.

Rend Life

Starting at 6th level, nature does not gift you power anymore. Instead, you must take from it forcefully. You leech the world of its life force to channel your magics.

Whenever a creature within 30 feet of you dies, you may use your reaction to restore 1d4 hit points and gain temporary hit points equal to your Druid level plus your Constitution modifier.

Hollow

At 10th level your corrupted ways have eroded your soul to the point that you now are no more than an empty husk. Your creature type turns Undead and you count as such for the purpose of different spells and magical effects, such as Turn Undead.

You no longer grow older, not even by magical effects. You no longer need to eat, drink, sleep, or breathe and can spend 4 hours during a long rest doing light activities to gain the benefits of a long rest. You gain resistance to necrotic damage and immunity to effects which reduce your hit point maximum.

Whenever you roll a death save, you may expend 5 hit dice from your hit dice pool to make the roll with advantage.

Defiler of Nature

At 14th level, your existence is now a dark mark upon the Druidic Circles, and you wound the land with your stolen power. As an action, once per long rest, you may leech the life from the land around you to regain a number of hit dice equal to 1 plus your Wisdom modifier. 

Additionally, whenever you deal damage, you may sacrifice a number of hit dice from your hit dice pool up to your Wisdom modifier to deal an additional 1d10 necrotic damage per hit die sacrificed.