Rank 1: Reduces the energy cost of your Backstab and Ambush abilities by 4 and the energy cost of your Hemorrhage by 1, and increases all damage done by 1%.

Rank 2: Reduces the energy cost of your Backstab and Ambush abilities by 8 and the energy cost of your Hemorrhage by 2, and increases all damage done by 2%.

Rank 3: Reduces the energy cost of your Backstab and Ambush abilities by 12 and the energy cost of your Hemorrhage by 3, and increases all damage done by 3%.

Rank 4: Reduces the energy cost of your Backstab and Ambush abilities by 16 and the energy cost of your Hemorrhage by 4, and increases all damage done by 4%.

Rank 5: Reduces the energy cost of your Backstab and Ambush abilities by 20 and the energy cost of your Hemorrhage by 5, and increases all damage done by 5%.