Source: Player's Handbook
Prerequisite: Level 4+
You gain the following benefits.
Ability Score Increase. Increase your Strength or Dexterity score by 1, to a
maximum of 20.
Weapon Proficiency. You gain proficiency with two weapons of your choice.
Mastery Property. Your training with weapons allows you to choose to gain
a mastery property from your choice of two kinds of Simple or Martial weapons that you have
proficiency with.
Fighting Style. You gain a Fighting Style
Feat of your choice.
Battle Maneuver. You gain a Maneuver
Option of your choice and one Superiority Dice, which are d8s, and are used for your
Maneuvers. You regain your Superiority Dice after you finish a Short or Long Rest.