Circle of Necrobotany

 There are some Druids who view the world as a balance of life and death, light and darkness, growth and decay. They tread the hallowed grounds of long forgotten graveyards and the blood-soaked soils of the battlefields of old, uncovering hidden arcane knowledge where the veil between worlds is at its thinnest. With their Necrotic magic they weave brambles and vines through skeletal remains, raising them from the dead and reclaiming them for nature. These nomadic shamans wander the land, banished by cloisters and covens alike for their taboo ways, but at least they have the spirits to keep them company. 

Necrotic Recovery

Starting at 2nd level, you can regain some of your magical energy by sitting in meditation and communing with the spirits beyond the veil. During a short rest, you choose expended spell slots to recover. The spell slots can have a combined level that is equal to or less than half your druid level (rounded up), and none of the slots can be 6th level or higher. You can’t use this feature again until you finish a long rest.

For example, when you are a 4th-level druid, you can recover up to two levels worth of spell slots. You can recover either a 2nd-level slot or two 1st-level slots.

Necrotic Wild Shape

You have grown so accustomed to death that you choose to reveal your reverence through your Wild Shape. It will always be undead, a rotting corpse with visible bone, vines knitting the skeleton together where the tendons no longer exist. Because of this, you are vulnerable to elemental damage, but immune to necrotic attacks.

Circle Spells

Your mystical connection to the veil infuses you with the ability to cast certain spells. At 3rd, 5th, 7th, and 9th level you gain access to circle spells connected to the balance of life and death.

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.

Spirit's Stride

Starting at 6th level, moving through nonmagical difficult terrain costs you no extra movement. You can also pass through nonmagical plants without being slowed by them and without taking damage from them if they have thorns, spines, or a similar hazard.

In addition, you have advantage on saving throws against plants that are magically created or manipulated to impede movement, such those created by the entangle spell.

Necrotic Ward

When you reach 10th level, you can’t be frightened by undead, and you are immune to poison and disease.

Necrotic Sanctuary

When you reach 14th level, undead creatures sense your connection to the veil and become hesitant to attack you. When an undead creature attacks you, that creature must make a Wisdom saving throw against your druid spell save DC. On a failed save, the creature must choose a different target, or the attack automatically misses. On a successful save, the creature is immune to this effect for 24 hours.

The creature is aware of this effect before it makes its attack against you.