Scourge

Magic is phenomenon that brings about the creation of many. Your magic, however, takes a slightly different form. You are an omen of destruction, your magic stemming from long-forgotten entities who desire nothing more than to reduce everything, including magic itself, into nothingness. Perhaps you or an ancestor were cursed to emanate this power,  or perhaps this power is the result of a deal made to enact the will of a calamitous being in exchange for power.
As a power that extinguishes both vitality as well as magic, Scourge Sorcery is feared by many but especially other magical casters. Many of those sorcerers who hold these abilities find themselves in a threatening existence, and as such, may seek to obfuscate the true nature of their magic. However, this task may prove difficult as they possess unique ways of channeling their magics.

Aspect of Desolation

Scourge Magic

You learn additional spells when you reach certain levels in this class, as shown on the Scourge Spells table. Each of these spells counts as a Sorcerer spell for you, but it doesn't count against the number of Sorcerer spells you know.

Scourge Spells:
1st Level: Hex, Inflict Wounds
3rd Level: Silence, Wither and Bloom
5th Level: Counterspell, Dispel Magic
7th Level: Blight, Banishment
9th Level: Negative Energy Flood, Circle of Power

When you reach 3rd level, you can cast these spells using spell slots as normal, or by expending a Sorcery Point per level of the spell's casting. Furthermore, when you cast a spell in this way, you can make one attack as part of the casting of the spell. Using Sorcery Points, you can cast these spells at levels higher than their base level, but you can only do so for levels which you have spell slots for.

Fist of the Void

Starting at 1st level, sinister energy flows through your body consistently and surges out at key moments, empowering your unarmed attacks. Your unarmed strikes now use your charisma modifier for attack and damage rolls, the damage die changes to a d8, as well as dealing necrotic damage. Enemies who are immune to necrotic damage are instead treated as if they have resistance to necrotic damage when they take necrotic damage from your unarmed strikes or spells from your scourge magic feature.

Vitality of the Void

Starting at 1st level, you have temporary hitpoints equal to 5 + your charisma modifier per sorcerer level, to a maximum of 5 + your charisma modifier per sorcerer level. Temporary hitpoints from other effects like spells including False Life can stack on top of these hitpoints. However, while no temporary hitpoints remain, you are vulnerable to any and all damage you take.

Furthermore, you do not get any bonuses to your armor class from armor/shields, spell effects, class features, racial bonuses, or feats and your hitpoints can no longer be recovered during short rests.
The temporary hitpoints can be replenished by any healing spells that would typically be unable to replenish temporary hitpoints up to your temporary hit point maximum. They are fully replenished from a long rest, and are partially replenished during a short rest by an amount equal to half of your maximum temporary hitpoints, rounded up.

Ravenous Erasure

Starting at 6th level, the power of erasure surges outward from your body, distorting space around you and aiding your movements. As a bonus action, you can enter the Ravenous Erasure state for the next minute. You gain the following benefits for the duration:

• You can attack twice, instead of once, whenever you take the Attack action on your turn
• Your movement speed increases by 20 feet
• Your movements no longer trigger attacks of opportunity
• You have advantage on all dexterity saving throws against spells or being grappled

While Ravenous Erasure is active, you cannot cast any spells other than the spells from your Expanded Spell List, but you can concentrate on any spells cast prior to invoking Ravenous Erasure. You can use this feature once per long rest, and, if you have no uses remaining, by expending 5 Sorcery Points.

Potent Destruction

Starting at 14th level, the power of destruction that resides within you behaves hungrier, seeming to consume the magical essence of creatures you strike. While Ravenous Erasure is active, you gain additional benefits:

• Whenever you hit a creature with an unarmed strike, you can expend any number of Sorcery Points. That creature must then make a Charisma Saving Throw against your Spell Save DC. On a failed save, that creature cannot cast any spells for a number of rounds equivalent to the number of Sorcery Points spent for this feature.
• Your movement speed increases by an additional 20 feet
• You have resistance to all damage from magical sources

Existential Rejection

Starting at 18th level, the power of erasure has reached the apex of its potential. You now gain the ability to unleash an ultimate attack with a potentially grave cost. Select a number anywhere from 1 to the maximum amount of Temporary Hitpoints gained from the class feature Vitality of the Void. This attack's damage is equal to 2 times that number. Choose one creature within melee range. They must make a Charisma saving throw against your Spell Save DC, for which they have disadvantage. You must also make a Charisma saving throw against your Spell Save DC,  for which you have advantage. On a failure, you/your target takes the full necrotic damage of this ability, and on a success, you/your target takes half necrotic damage of this ability. The damage cannot be reduced or negated in any way. If this damage drops any creature (including yourself) to 0 HP, they are removed from existence, leaving not even dust or a soul behind, and they cannot be revived or resurrected in any way.
Assuming you survive this attack, you cannot cast it again until after 3 long rests.