Prerequisite: Dexterity 15

Your Strength or Dexterity score increases by 1, to a maximum of 20.

When you make a melee attack roll against a creature while you’re Heavily Obscured from it or while it’s Surprised, the critical hit range of that attack is increased by one.

Finally, after reducing a hostile creature’s hit points to 0 with damage from an Agile or Main-Handed melee weapon, for the next minute: that weapon’s damage die size increases by one, and your base walking speed increases by 10 feet (to a maximum total of 45 feet).