School of Muscles

The School of Muscle is an unconventional arcane tradition that combines the art of wizardry with physical strength and prowess. Wizards of this school understand that knowledge alone is not enough; it must be paired with the power to enforce it. These spellcasters dedicate themselves to rigorous physical training, enhancing their magical abilities with sheer muscle power. They are as comfortable in a brawl as they are in a library.
(This subclass wasn't originally designed for serious play, it was more for my own fun making it. However, if you're interested, feel free to provide feedback in the comments and make any changes you like. Enjoy!)

Enhanced Physicality

You trained your body in both magical and physical ways, while you are not wearing any armor, your Armor Class equals 10 + your Intelligence modifier + your Constitution modifier. You can use a shield and still gain this benefit. Additionally, you can use your Intelligence modifier in place of Strength for Athletics checks, and you gain proficiency in Athletics if you do not already have it.

Punchcasting

Starting at 2th level, your unarmed strikes deal 1d4 damage, and you can use your Intelligence modifier instead of Strength for the attack and damage rolls. Additionally, once per turn when you hit a creature with your unarmed strike, you can cast a spell with a casting time of 1 action on the same creature as part of the attack action (rolling for the spell attack if needed). You can use this feature a number of times equal to your proficiency bonus per long rest.

Your Unarmed strikes damage dice increases to 1d6 when you reach 9th level on this class, and 1d8 on level 14th.

 

 

Adaptive Arcanist

At 6th level, being within 5 feet of a hostile creature no longer imposes disadvantage on your ranged spell attack rolls. Additionally, when you use your Punchcasting ability, you gain temporary hit points equal to your Intelligence modifier (minimum of 1).

Muscle Memory

Starting at 10th level, your physical training grants you extraordinary resilience. When a creature hits you with an attack, you can choose to add your Intelligence or Strength modifier to your AC against that attack. You can do this a number of times equal to your Strength modifier (minimum of 1) per long rest.

Additionally when you cast a spell that requires a melee spell attack, you can add your Strength modifier to the attack roll and damage roll.

Mythical Powerhouse

At 14th level, you become a paragon of both magical and physical might. Your unarmed strikes now  count as magical for the purpose of overcoming resistance and immunity to nonmagical attacks and damage. Additionally, immediately after you use your Punchcasting ability, you can choose one of the following benefits:

• You automatically pass the saving throw required by the spell (e.g., if you cast Fireball, you automatically pass the saving throw to halve the damage).
• You gain temporary hit points equal to four times the spell slot level used.
•  If the spell involves a melee spell attack, you can double your Strength modifier for the attack roll and damage roll.
• You can choose to change the damage type of the spell to bludgeoning, slashing, or piercing.

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