You can invoke an elven magic called the Bladesong, provided that you aren’t wearing medium or heavy armor or using a shield. It graces you with supernatural speed, agility, and focus.

You can use a bonus action to start the Bladesong, which lasts for 1 minute. It ends early if you are incapacitated, if you don medium or heavy armor or a shield, or if you use two hands to make an attack with a weapon. You can also dismiss the Bladesong at any time (no action required).

While your Bladesong is active, you gain the following benefits:

• You gain a bonus to your AC equal to your Intelligence modifier (minimum of +1).
• Your walking speed increases by 10 feet.
• You have advantage on Dexterity (Acrobatics) checks.
• You gain a bonus to any Constitution saving throw you make to maintain your concentration on a spell. The bonus equals your Intelligence modifier (minimum of +1).

You can use this feature a number of times equal to your proficiency bonus, and you regain all expended uses of it when you finish a long rest.

Notes: Bonus: Armor Class, Bonus: Speed (Walking), Advantage: Acrobatics, Bonus: Constitution Saving Throws