Level 3: Jolt to Life

When you cast Spare the Dying, you can modify the spell so that it sends a jolt of electricity through the target, reviving it. The target regains 1 Hit Point, and each creature in a 10-foot Emanation originating from the target makes a Dexterity saving throw against your spell save DC, taking Lightning damage equal to 1d4 plus half your Artificer level (round up) on a failed save or half as much damage on a successful one.

You can modify the spell this way a number of times equal to your Intelligence modifier, and you regain all expended uses when you finish a Long Rest.

Level 3: Reanimated Companion

Using Tinker's Tools and the remains of one or more previously living creatures, you can perform a 1 hour Rite to create a Reanimated Companion (see the stat block) through the power of necromancy and science. If you are interrupted while performing this Rite, you must start over to perform the Rite again. The companion takes form during the Rite in an unoccupied space within 5 feet of you, and becomes active when the Rite is completed. You determine the companion's appearance; your choices don't affect the companion's game statistics.

The companion is Friendly to you and your allies and obeys you. It lasts until you finish a Long Rest or until you take a Magic action to dismiss it early, at which point it harmlessly collapses into a pile of parts and viscera. It immediately drops to 0 Hit Points and dies (triggering its Death Burst trait) if you die. You can have only one companion at a time.

The Companion in Combat. In combat, the companion acts during your turn. It can move and take its Reaction on its own, but the only action it takes is the Dodge action unless you take a Bonus Action to command it to take an action. If you have the Incapacitated condition, the companion acts on its own and isn't limited to the Dodge action.

Level 5: Improved Reanimation

Each time you create a Reanimated Companion, you must choose one of the following options. The resulting companion is altered as indicated for the chosen option.

*Bloated. You can make a big tumefied companion with Large size, Strength 18 (+4), and Dexterity 6 (-2). Whenever the companion hits a Large or smaller creature, that creature can also be pushed up to 10 feet away from the companion. Finally, the companion's Death Burst trait deals an additional 2d6 Poison damage.

*Creepified. You can make a skittery-scary companion with Strength 9 (-1), Dexterity 15 (+3), and proficiency with Perception. The companion's Speed increases to 45 feet, and it gains a Climb Speed equal to its Speed. It can climb difficult surfaces, including along ceilings, without needing to make an ability check. In addition, whenever a creature of your choice starts its turn within a 10-foot Emanation originating from your companion, the creature must succeed on a Wisdom saving throw against your spell save DC or have the Frightened condition until the start of its next turn.

*Juiced. You can make an alchemically juiced companion that has proficiency with all saving throws, and a Swim Speed equal to its Speed. The companion's Death Burst and Dreadful Swipe deal Acid damage instead of Necrotic damage, and whenever they are hit by an attack roll from a creature within 10 feet of it, the attacker takes Acid damage equal to your Intelligence modifier.

*Normalized. You can make a normal-seeming companion with Medium size, Intelligence 8 (-1), and Charisma 8 (-1). The companion speaks the languages you speak, and has proficiency with one skill of your choice that you are proficient with. If the companion looks like a member of a humanoid lineage they can pass as a living creature of that kind, but observers can succeed on an Intelligence (Investigation) ability check against your spell save DC to determine their true nature.

Level 5: Multiattacking Companion

When you command your companion to take the Dreadful Swipe action, the companion can use it twice.

Level 9: Strange Modifications

Each time you create a Reanimated Companion, you must choose one of the following options. The resulting companion is altered as indicated for the chosen option.

*Arcane Conduit. You can cast spells as though you were in the companion's space, but you must use your own senses. Once per turn, when you do so you can cause one target of the spell to take Lightning damage equal to you Intelligence modifier (minimum 1).

*Electrical Regulator. Once per combat, at the start of their turn your companion can regain a number of Hit Points equal to their Proficiency Bonus plus their Constitution modifier and then move up to their Speed without suffering Opportunity Attacks. If the companion is Prone, they may spend 5 feet of this additional movement to remove the condition.

*Life Conduit. As a Bonus Action during your turn or as a Reaction when you take damage, if your companion is on the same plane of existence you can cause it to lose Hit Points up to its current total. You regain an equal number of Hit Points. If your companion is reduced to 0 Hit Points, they immediately die (triggering their Death Burst trait). Once you have used this ability, you must complete a Short or Long Rest before using it again.

*Walking Bomb. As a Bonus Action during your turn you can command the companion to move up to its Speed and then explode, triggering its Death Burst trait. The resulting Death Burst has a 20-foot Emanation, deals additional damage equal to half the number of Hit Points the companion had remaining, and creatures that succeed on their saving throw take half damage. The companion is detroyed by this.

Level 15: Promethean Reanimation

You have mastered the science of revivification, granting you the following benefits.

Electrified Revival. When you cast Revivify or Raise Dead during a lighting storm or with access to a specialized laboratory, you don't need Material components.

Galvanic Principles. Evocation spells of level 6 and below that deal Lighting damage are considered to be prepared by you and on your spell list for purposes of making and using Spell Scrolls. However, if such a spell offers a choice of damage type, Lightning is the only available choice for you.

Galvanized Burst. Your Reanimated Companion's Death Burst deals an additional 2d6 Lightning damage. Also, damage dealt by your companion ignores Resistance.