To unlock this Trophy you need to Complete the Cardassian Struggle story arc (as noted in the description) which is comprised of the following 10 missions...
- “Lost and Found”
- “Spoils of War”
- “Jabberwocky”
- “The Factory”
- “The New Link”
- “Second Wave”
- “Of Bajor”
- “Operation Gamma”
- “Facility 4028”
- “Boldly They Rode”
This story arc can be completed by Federation, Klingon and Romulan characters at level 35 or above.