Source: Arcana Unleashed
Command the Powers of Death and Undeath
You explore the forces of life, death, and undeath. As a necromancer, you learn to manipulate the energy that animates all creatures, and you draw increasing power from the forbidden secrets in your spellbook. Though many see Necromancers as menacing or villainous, not all Necromancers are evil.
Level 3: Necromancy Savant
Choose two Wizard spells from the Necromancy school, each of which must be no higher than level 2, and add them to your spellbook for free.
In addition, whenever you gain access to a new level of spell slots in this class, you can add one Wizard spell from the Necromancy school to your spellbook for free. The chosen spell must be of a level for which you have spell slots.
Level 3: Necromancy Spellbook
Your spellbook’s necromantic secrets grant you additional powers. You gain the following benefits.
Necrotic Resistance. You have Resistance to Necrotic damage.
Undead Familiar. The Find Familiar spell appears in your spellbook. When you cast the spell, you choose one of the normal forms for your familiar or one of the following special forms: Skeleton or Zombie (see appendix B of the Player’s Handbook for the familiar’s stat block). When you choose one of the normal forms, you can choose Undead as its creature type.
Additionally, when you take the Attack action, you can forgo one of your own attacks to allow your familiar to make one attack of its own with its Reaction.
Undead Vitality. When you cast a Necromancy spell using a spell slot, you can choose an Undead creature you can see within 60 feet of yourself to regain a number of Hit Points equal to the level of the spell slot expended plus your Wizard level.
Level 6: Grave Power
You have discovered more necromantic insights and inscribed them in your spellbook. While holding your spellbook, you gain the following benefits.
Grave Resilience. When you use Arcane Recovery, your Exhaustion level, if any, decreases by 1.
Overwhelming Necrosis. Damage from your Wizard spells and Wizard features ignores Resistance to Necrotic damage.
Level 6: Undead Thralls
You always have Animate Dead prepared and can cast it without expending a spell slot, but you must finish a Long Rest before you can cast it in this way again. Whenever you start casting the spell, you can increase the spell’s effective level by 1.
In addition, while holding your spellbook, you gain the following benefits.
Undead Fortitude. Whenever you cast a Necromancy spell that creates or summons an Undead, the Undead’s Hit Point maximum and current Hit Points increase by a number equal to your Intelligence modifier plus half your Wizard level (round down).
Withering Strike. Whenever an Undead you control within 60 feet of you hits a creature with an attack roll, the Undead deals extra Necrotic damage equal to your Intelligence modifier (minimum of 1 Necrotic damage).
Level 10: Harvest Undead
You have learned more secrets about the nuances of life and death. Immediately after you become Bloodied but aren’t reduced to 0 Hit Points from taking damage, you can take a Reaction to reduce an Undead creature under your control that you can see to 0 Hit Points. You then immediately regain a number of Hit Points equal to your Wizard level.
Level 14: Death's Master
Abstruse rituals within your spellbook allow you mastery over undeath. While holding your spellbook, you gain the following benefits.
Bolster Undead. As a Bonus Action, choose any number of Undead you have created or summoned with a Necromancy spell that are within 60 feet of you. Those Undead each gain Temporary Hit Points equal to your Wizard level. Once you use this Bonus Action, you can’t do so again until you finish a Long Rest.
Extinguish Undead. When an Undead creature you can see is reduced to 0 Hit Points, you can cause it to explode with necrotic energy. Roll a number of d6s equal to half the creature’s unexpended Hit Dice (round up, minimum of 1d6), and add them together. Each creature in a 10-foot Emanation originating from the Undead makes a Dexterity saving throw. On a failed save, a target takes Necrotic damage equal to the number rolled and can’t take Reactions until the start of its next turn. On a successful save, a target takes half as much damage only. When you use this feature to explode an Undead creature you don’t control, you must take a Reaction and expend a level 5+ spell slot to do so.