Split Identity

Through reckless experimentation, you have permanently altered your body and soul, tying it to another identity hidden within. Whether caused by rage, boredom, intention, or some other trigger, you can enter this other form, augmenting your combat abilities and weakening your mental ones. 

Bonus Proficiencies

You gain proficiency in Alchemist's Supplies, Martial Weapons, and Improvised Weapons.

Alter Ego

As part of your experimentation, you have gained an Alter Ego that excels at physical combat, at the cost of some of your mental fortitude.

At third level you can assume this Alter Ego form as a bonus action. While you are transformed, you gain the following benefits:

- Your Strength and Intelligence scores swap.

- Your unarmed strikes do bludgeoning damage equal to 1d6 + your Strength modifier.

- You gain a number of temporary hit points equal to your 5 times Artificer level.

- You have advantage on Strength saving throws, Strength checks, Charisma (Intimidation) checks.

This transformation lasts for 10 minutes, and can not be ended early unless you become unconscious. You can use this transformation a number of times equal to your Intelligence modifier, and regain all expended uses on a long rest. 

Transformative Fury

At 5th level, when you assume your Alter Ego form, you grow one size larger. If you lack the room to grow larger, you remain at your current size. Additionally, whenever you take the Attack action on your turn, you may make one additional attack as part of that action. Once on each of your turns, one of your attacks with a weapon or an unarmed strike can deal an extra 1d6 damage to a target on a hit.

Forced Transformation

At 9th level, your Alter Ego begins to poke through in times of need. When you fail a saving throw caused by a hostile creature, you can choose to succeed instead. If you are not in your Alter Ego form, you transform as part of this effect without expending a use of your Alter Ego feature. Once you use this feature, you can not do so again until you finish a short or long rest. 

Additionally, you can now end your Alter Ego transformation early by spending an action to calm down. 

Harmonious Identities

At 15th level, you and your Alter Ego have learned to work together. You now have unlimited uses of Alter Ego form. When you transform, your Strength score becomes equal to your Intelligence modifier, rather than them swapping.