You have always been able to step into the shadows and melt out of sight, it was a knack that helped you survive a troubled childhood and now you use it to make a living.
Tier 1: Shadow Stalk (2 Speed points).
Step unseen into the shadows, moving swiftly but silently and stalk your prey.
Tier 2: Shadow Speed (3 Speed Points).
Use the shadows to augment your speed and take two actions in a round.
Tier 3: Shadow Blade (2 Speed Points).
Conjure a blade of pure Shadow which extends from your arm, the blade counts as a Medium Weapon from which you take no penalty.
Tier 4: Enshroud (3 Might Points if Attacking, 2 Speed if Defending).
Either Enshroud an enemy to prevent their taking any action or Enshroud a friend to prevent their taking damage or to allow them to follow you into the Shadows.
Tier 5: Shadow Sling (2 Speed Points).
Create and sling a projectile of pure shadow, dealing 2 damage to target and dazing them for 1 round.
Tier 6: Shadow Mastery (4 Speed Points).
Your shadow detaches itself and takes a more corporeal form to aid you. Shadow is a level 3 creature which lasts for 5 rounds.
Attack with Shadow Blade or Shadow Sling, each attack reduces lifespan by one round.