Armor of the Archmage

You magically enlarge the suit of armor and cause it to fit around you, and a spectral greatsword appears in your hand. For the duration, you have proficiency with heavy armor, your Armor Class is 18, and any critical hit against you is a normal hit.

As an action, you can make two attacks with the sword. Make a melee spell attack against a target within your reach. On a hit the target takes 2d10 force damage. Additionally, as a bonus action, you can change the sword into a longbow. While it is in longbow form you can use an action to make two attacks. Make a ranged spell attack with a normal range of 300 feet and no long range. On a hit the target takes 2d8 force damage. While the weapon is in longbow form you can use a bonus action to change it back into a greatsword.