Old Blood (5e Subclass)
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You may have come from a family of witches or magi. Or perhaps your family hasn't produced a mage of any kind from your understanding. Regardless, your ancestors have granted you power that courses through your blood and their spirits.
Thicker Than Water
Your blood is incredibly good at staying within you and remaining untainted. Beginning at 1st level, you gain resistance to necrotic damage. Additionally, when you deal damage with a cantrip that deals necrotic damage, you may add your Charisma modifier to the damage roll.
When you reach 3rd level in this class, you learn the Lesser Restoration spell which doesn't count against your number of sorcerer spells known. You may target only yourself, and casting this spell does not require verbal or somatic components. After ending a condition this way, you may expend 3 sorcery points to gain a number of hit points equal to your sorcerer level + your Constitution modifier (minimum of 1).
Your magic is strongly tied to your ancestral line and spirits in general. Starting at 6th level, you can cast the Speak with Dead spell. Additionally, you may call upon your ancestors guidance, granting you proficiency in two skills or tools for 10 minutes. If you choose skills you already possess, you may instead grant yourself expertise for the duration. You may use both parts of this feature once before completing a short or long rest.
(In terms of flavor, you may ask your DM to give you two skills at random, gifted from an ancestor you didn’t know you had or perhaps one that felt the need to intervene.)
Ghosts of the Past
Your spells ignore resistance to necrotic damage. Additionally, beginning at 14th level, as an action you may expend 6 sorcery points to make yourself incorporeal for one minute. While under this effect, you can move through objects and creatures as if they were difficult terrain. If this effect ends while you are within a structure, you are shunted to the nearest open space and take 1d10 force damage for every 5 feet you are shunted to a maximum of 10d10.
Beginning at 18th level, you gain the following benefits:
When you deal damage with a touch spell of 1st level or higher, you deal an additional 2d8 necrotic damage. If the spell already deals necrotic damage, increase the extra damage to 3d8. When you deal this damage, you gain temporary hit points equal to half the extra necrotic damage dealt.
You gain immunity to poison damage and the poisoned condition.
You can cast spells without material components costing no more than 500gp. For every 10gp (rounded up) the component would cost, you lose one hit point, and your hit point maximum decreases by the same amount. These hit points can only be restored by a completing a long rest.