Some mages are drawn to darker forces than the average mage. They choose to focus on the dark arts of necromancy, the enemy of life itself. Mages who follow this path can conjure festering diseases, reanimate the dead, or fire bolts of dark energy. Some choose to become masters of skeletal minions, while others choose instead to focus their dark power on themselves.
When you choose this specialization at 2nd level, you gain the Hand of Decay cantrip, which doesn't count against the number of mage cantrips you know.
Your study into the necromantic arts has granted you spells not typically known by other mages. When you take this subclass, you add a number of spells, listed in the Spells section below, to the mage spell list.
Starting at 2nd level, you learn a harsh curse to place on your enemies. As a bonus action, choose one creature you can see within 30 feet of you. The target is crippled for 1 minute. The effect ends early if the target dies, you die, or you are incapacitated. Until the effect ends, the target suffers from the following effects:
It's movement speed is reduced by half.
On its turn, it can use either an action or a bonus action, not both.
When it would deal damage with its attacks or spells, it must roll twice and use the lower result.
Once you use this feature, you cannot do so again until you finish a short or long rest.
Starting at 2nd level, you have advantage on saves versus disease. Your regular interactions with the dead and the Plague of Undeath has given you better resistance to their effects.
Starting at 6th level, you gain one of the following features of your choice:
You are immune to diseases and are resistant to necrotic damage.
Additionally, when you cast a necromancy spell that is 1st level or higher and only affects a single enemy, and the spell hits the target or the creature fails their save, you can choose to infect them with a virulent disease. You choose which of the diseases detailed in the "Necromancer Plagues" section below to inflict on your target, which takes effect immediately. At the end of each of the creature’s turns, it can make the saving throw specified in the disease’s description. On a failure, the creature takes 1d6 necrotic damage per spell level of the infecting spell, up to 5d6, and continues to suffer the effects of the disease. On a success, the creature takes no damage and suffers none of the disease’s effects until the end of its next turn. The disease ends after 1 minute or when the creature has made three successful saving throws against the disease.
If a target is inflicted with a new necromancer plague while already suffering from an one, the original one ends and the new one takes effect.
If a creature dies while under the effects of these plagues, any spell that animates undead requires no material components in order to raise them.
Blood Plague; The diseased creature can’t regain hit points. Whenever it is damaged by a melee attack, the attacker gains temporary hit points equal to your Intelligence modifier plus half your mage level. Blood Plague is resisted by Constitution.
Crypt Blight; The diseased creature can use either an action or a bonus action on its turn, not both. Regardless of the creature’s abilities or magic items, it can’t make more than one melee or ranged attack during its turn. Crypt Blight is resisted by Wisdom.
Delirious Fever; The diseased creature’s speed is halved, and it can’t take reactions. Delirious Fever is resisted by Dexterity.
You add the Animated Dead spell to your spellbook if it is not there already. If it is, choose another 3rd-level spell of the Study of Necromancy and add it to your spellbook.
You can cast animate dead without a body, using a shard of bone instead. If you cast the spell this way, you can only create skeletons and you can create an additional skeleton.
You can choose to cast animate dead as an action in place of its 1-minute casting time. You can do so a number of times equal to your Intelligence modifier (minimum 1), and regain all uses when you finish a long rest.
Whenever you create an undead using a necromancy spell, it has the following additional features.
The creature’s hit point maximum is increased by an amount equal to your mage level.
The creature adds half your proficiency bonus to its AC and its attack rolls, and adds your proficiency bonus to its weapon damage rolls.
When you reach 10th level, you gain one of the following features, depending on which ability you selected at 6th level.
As a bonus action, you can summon a spectral plague cauldron at a point you can see within 30 feet, spewing a deathly orange cloud of disease in a 10 foot cube. The cauldron lasts for 1 minute, until you use this feature again, or until you use a bonus action to dismiss the cauldron.
Whenever a creature moves into the cube or starts its turn there, that creature takes 1d8 necrotic damage, unless the creature succeeds on a Constitution saving throw against your spell save DC. A creature can take this damage no more than once per turn.
When you reach level 14, this damage increases to 1d10.
When you cast the Animate Dead spell, you can choose to animate a more complex skeleton. When you cast it as a 5th level spell, you can create a skeleton of CR 2 or below, and the max CR increases by 1 for every 2 spell levels above 5th. When you use animate dead to create or reassert control on an advanced skeleton, count it as a number of skeletons equal to its CR times 4. For example, a skeletal warrior has a CR of 1 and would count as 4 skeletons.
You can also use your reaction and expend a spell slot of 1st or higher level to reform a skeleton you animated that was killed but not completely destroyed, restoring it to unlife. It reanimates with a number of hit points equal to 5 times the spell level expended; if this would bring it above its normal maximum hit point total, it gains the remainder as temporary hit points that last until your next long rest.
At 14th level, you gain one of the following benefits depending on which feature you chose at 6th level:
When a creature afflicted with one of your necromancer plagues dies, you can spread the disease to a different creature you can see within 30 feet of the dead creature, provided you aren’t incapacitated. This counts as a new instance of the disease for the sake of its duration and the number of saving throws needed to end it prematurely.
Any undead you summon or create has 30 temporary hit points. They regain these temporary hit points when you finish a long rest.
Additionally, they add your whole proficiency bonus to Armor Class and attack rolls.