The School of Necromancy explores the cosmic forces of life, death, and undeath. As you focus your studies in this tradition, you learn to manipulate the energy that animates all living things. As you progress, you learn to sap the life force from a creature as your magic destroys its body, transforming that vital energy into magical power you can manipulate.

Most people see necromancers as menacing, or even villainous, due to the close association with death. Not all necromancers are evil, but the forces they manipulate are considered taboo by many societies.

Necromancer Initiate

You know the chill touch and spare the dying spells. These count as Wizard cantrips for you but don't count against your spells known. 

Undead Thrall

As an action, you can magically summon an undead Thrall. It appears in an unoccupied space of your choice within 60 feet of you.

The Undead Thrall is friendly to you and your companions, and it obeys your commands. See its game statistics in the accompanying Undead Thrall stat block, which uses your proficiency bonus (PB) in several places. The Undead Thrall takes on the form of a ghostly incorporeal creature. You can determine the cosmetic characteristics of the Undead Thrall; such changes have no effect on its game statistics.

In combat, the Undead Thrall shares your initiative count, but it takes its turn immediately after yours. It can move and use its reaction on its own, but the only action it takes on its turn is the Dodge action, unless you take an action or bonus action on your turn to command it to take another action. That action can be one in its stat block or some other action. When you command the Undead Thrall to take an action, such as the Attack action, it will continue to take that action until you use another action or bonus action to command it to take another action, or until it is otherwise unable to. If you are incapacitated, the Undead Thrall can take any action of its choice, not just Dodge.

The Undead Thrall remains until it is reduced to 0 hit points, until you use this feature to summon the drake again, or until you die. Anything the Undead Thrall was wearing or carrying is left behind when the Undead Thrall vanishes. You can also use an action to temporarily dismiss your Undead Thrall. When you summon it again the Undead Thrall reappears with the same statistics as when it was dismissed, including any lost hit points. 

Once you summon the Undead Thrall, you can’t do so again until you finish a long rest, unless you expend a spell slot of 1st level or higher to summon it. When you summon it using a spell slot it reappears with hit points equal to 10 times the spell slot level (if you previously dismissed your undead thrall it instead regains a number of hit points equal to 10 times the spell level).

Necromancer Adept

Starting at 6th level, your arcane research has led to greater knowledge of necromancy. You learn two necromancy spells of your choice from any class list, which are treated as Wizard spells for you but do not count against your spells known. The spell must also be a level of which you can cast. 

You learn an additional necromancy spell of your choice at 10th and 14th level. 

Inured to Undeath

Beginning at 10th level, you have resistance to necrotic damage, and your hit point maximum can't be reduced. You have spent so much time dealing with undead and the forces that animate them that you have become inured to some of their worst effects.

Corporeal Host

Starting at 14th level, your Undead Thrall can possess the corpses of dead creatures. As an action you can summon your Undead Thrall to possess the corpse of a creature whose challenge rating was equal to or lower than your proficiency bonus within 60 feet of you, rather than appearing in an unoccupied space.

Your Undead Thrall uses the stat block of this creature with the following exceptions: it retains its alignment, personality, and Charisma, Intelligence and Wisdom ability scores, it retains its saving throw proficiencies, it uses your proficiency bonus instead of the possessed creatures, its creature type is undead, and any ability of the possessed creature that has a listed DC instead uses your spellcasting DC. 

If your Undead Thrall is reduced to 0 hit points while possessing a corpse, is effected by a spell such as dispel evil and good, or you command it to leave the body (no action required) the Undead Thrall is forced out of the corpse, which leaves behind the inanimate corpse and your Undead Thrall appears in an unoccupied space within 30 feet of the corpse. If it reverts as a result of dropping to 0 hit points, any excess damage carries over to its normal form. 

Once your Undead Thrall possess a corpse it cannot do so again until you finish a long rest.