From publisher blurb:
The core set of Phoenix: Dawn Command is only designed to support four players. This twenty card expansion adds the critical Action Cards you need to add an additional player using a Strength-based School (Bitter, Durant, or Forceful). This includes the following:
8 Strength cards (two each of values 2-5)
8 Grace cards (two each of values 2-5)
4 Trait cards: Thrill Seeker, Swashbuckler, Feral and Barbarian.
The Grace and Strength cards are identical to those in the core set. The Trait cards use the same art as those in the core set but have unique text. The cards are of similar quality to the cards in the core set, but they are cut slightly differently; they can be mixed with core cards, but the corners are rounder.