Knowledge is dangerous! Especially when don’t know what you are doing!
Path of the Savant
A little knowledge is a dangerous thing. You’ve learned… enough. The wizard taught you a some things and some things took. Not much, but some. You got you a book, you got you some learning, and know you gonna hit people with both!
Starting when you choose this path at 3rd level, you get a spellbook with two wizard cantrips. When you start to rage, you can stare at the book for a bit, cram a spell in your brain and you go hog wild. As a bonus action while raging, you can cast that cantrip. The DC for any save is based on your Constitution and spell attacks are made using your Constitution modifier. When your rage ends, you suffer one level of exhaustion as your head hurts. You can copy new spells into your spellbook as a wizard normally does.
Beginning at 6th level, you gain proficiency in Arcana and History. You also gain detect magic into your spellbook and can cast that spell as normal without being in a rage.
Beginning at 10th level, while raging you gain advantage on saving throws against magic spells and effects as your heightened understanding of magic in your rage state lets you see the flow of magic.
Starting at 14th level, you gain the ability to cast 1st level wizard spells and can copy two into your spellbook when you get this ability. When you rage you can choose to learn a 1st level spell instead of a cantrip. If you do, you can cast that spell as a bonus action, but you gain two levels of exhaustion when the rage ends instead of one.