The Arcane Engineer wields the power of energy cores—arcane constructs that harness raw magical energy for both offense and defense. By channeling these volatile cores, they can unleash devastating blasts, reinforce allies with protective fields, or manipulate energy to control the battlefield. Masters of innovation, Arcane Engineers are as adept at crafting ingenious solutions as they are at harnessing destruction. Their versatile arsenal makes them invaluable allies and formidable foes.

Arcane Engineer Spells

You always have certain spells prepared after you reach particular levels in this class, as shown by the Arcane Engineer Spells table. These spells count as artificer spells for you, but they don’t count against the number of artificer spells you prepare.

Arcane Engineer Spells

Artificer Level	Spell
3	Chromatic Orb, Shield
5	Misty Step, Ray of Enfeeblement
9	Lightning Bolt, Counterspell
13	Wall of Fire, Ice Storm
17	Wall of Force, Cone of Cold

Arcane Engineer Spells

3rd-level Arcane Engineer feature

You always have certain spells prepared after you reach particular levels in this class, as shown by the Arcane Engineer Spells table. These spells count as artificer spells for you, but they don’t count against the number of artificer spells you prepare.

Artificer Level	Spell
3	Chromatic Orb, Shield
5	Misty Step, Ray of Enfeeblement
9	Lightning Bolt, Counterspell
13	Wall of Fire, Ice Storm
17	Wall of Force, Cone of Cold

Energy Core Harness

3rd-level Arcane Engineer feature

When you choose this subclass at 3rd level, you gain the ability to craft and utilize special devices called Energy Cores. These cores are small, magical orbs that channel and store various forms of energy.

Energy Core: You learn to create Energy Cores as part of your crafting abilities. You can craft one Energy Core during a short or long rest, which takes up a simple tool slot. Energy Cores come in different types, each granting a different effect when used. You can carry a number of Energy Cores equal to your Intelligence modifier (minimum of one).

You can expend a spell slot to create another Energy Core as a bonus action.

Types of Energy Cores:

1. Fire Core: Deals fire damage and applies the burning condition
2. Ice Core: Deals cold damage and reduces speed by 15ft
3. Lightning Core: Deals lightning damage and applies the blinded condition
4. Force Core: Deals force damage and applies the prone condition

1. Thunder Core: Deals thunder damage and applies the confused condition.

Each core has three uses that require an action to use, each core can only be used once. The uses are listed in the table below:

Use Name	Effect
Strike	Choose a point within 60 feet of you. Each creature within a 10-foot radius of that point must make a Constitution saving throw. On a failed save, a creature takes 3d8 damage equal to the type of core used and is pushed 10 feet away from the centre of the blast. On a successful save, it takes half as much damage and is not pushed. The damage increases to 4d8 at 11th level and 5d8 at 17th level.
Wave	Create a 15ft cone. Creature within the area must make a Constitution saving throw. On a failed save, a creature takes 2d8 damage equal to the type of core used and has the appropriate status effect applied for 1 minute. On a successful save, the creature takes half as much damage and is not affected by the status effect. The creature can make repeated saves at the end of its turn. The damage increases to 3d8 at 11th level and 4d8 at 17th level.
Shield	You create a protective barrier of energy around yourself. For 1 minute, you gain temporary hit points equal to your artificer level + your Intelligence modifier. Additionally, any creature that hits you with a melee attack while you have these temporary hit points takes 1d8 damage equal to the type of core used. The damage increases to 2d8 at 11th level and 3d8 at 17th level.

Core Amplification

5th-level Arcane Engineer feature

You can now enhance the effects of your Energy Cores. As a bonus action, you can expend a spell slot to amplify the power of an Energy Core you are holding. The core’s effect increases in power as follows:

• 1st-level spell slot: Increase the damage of Strike or Wave by 1d8.
• 2nd-level spell slot: Increase the damage of Strike or Wave by 2d8.
• 3rd-level spell slot: Increase the damage of Strike or Wave by 3d8. The range on Strike is improved to 90ft and the cone of Wave is increased to 30ft

Energy Convergence

9th-level Arcane Engineer feature

You have mastered the art of combining and directing various forms of energy. You can now perform an Energy Convergence once per long rest, allowing you to channel multiple Energy Cores simultaneously to create a powerful, combined effect.

Energy Convergence Mechanics:

1. Channelling Multiple Cores: As an action, you can expend up to three Energy Cores you are carrying and activate them simultaneously. Each core’s effect is applied in a combined manner, creating a unique and powerful result. Choose the cores you want to converge and select one of the following effects based on the types of cores you use:
• Fire + Lightning: Inferno Storm
  You create a storm of fire and lightning in a 20-foot radius centered on a point you can see within 120 feet. Each creature in the area must make a Dexterity saving throw. On a failed save, a creature takes 4d10 fire damage and 4d10 lightning damage and is stunned until the end of its next turn. On a successful save, the creature takes half as much damage and isn’t stunned.
• Ice + Thunder: Frostquake
  You cause a violent explosion of ice and thunder in a 15-foot cone. Each creature in the area must make a Constitution saving throw. On a failed save, a creature takes 3d10 cold damage and 3d10 thunder damage and is knocked prone and pushed 10 feet away from you. On a successful save, the creature takes half as much damage and isn’t knocked prone or pushed.
• Force + Fire: Combustive Force
  You create a concentrated blast of magical force and fire. Choose a point within 100 feet of you. Each creature within a 10-foot radius of that point must make a Strength saving throw. On a failed save, a creature takes 5d10 fire damage and 5d10 force damage and is pushed 20 feet away from the point. On a successful save, the creature takes half as much damage and isn’t pushed.
• Lightning + Force: Lightning Surge
  You release a surge of lightning and force in a 30-foot line that is 5 feet wide. Each creature in the line must make a Dexterity saving throw. On a failed save, a creature takes 4d10 lightning damage and 4d10 force damage and is knocked back 15 feet. On a successful save, the creature takes half as much damage and isn’t knocked back.
• Thunder + Ice: Tempest Wave
  You unleash a wave of icy thunder that sweeps out in a 30-foot cone. Each creature in the area must make a Constitution saving throw. On a failed save, a creature takes 4d8 cold damage and 4d8 thunder damage, and has its speed reduced to 0 until the end of its next turn. On a successful save, the creature takes half as much damage and isn’t slowed.
2. Energy Fusion: When performing an Energy Convergence, you can choose to expend one additional spell slot of 3rd level or higher to enhance the effect. The damage of the chosen Energy Convergence effect increases by one additional die per spell slot level above 3rd, and the area of effect or range increases by 10 feet.

Example: If you expend a 4th-level spell slot for Inferno Storm, the damage increases to 5d10 fire and 5d10 lightning, and the radius increases to 30 feet.

Temporal Re-calibration

15th-level Arcane Engineer feature

Your mastery over energy manipulation has advanced. You can now perform a Temporal Recalibration once per long rest. As an action, you can recalibrate an Energy Core to allow it to be used again immediately, or you can use this feature to regain a spell slot of 3rd level or lower.

Additionally, once per short or long rest, you can choose to reset any expended Energy Cores you have, allowing you to use them again without crafting a new one.