Perfect World Entertainment and Cryptic Studios have revealed that Legacy of Romulus, a full Star Trek Online expansion, will launch on May 21st, 2013. The expansion allows players to begin as a Romulan or Reman and features a number of UI and trait enhancements. Additionally, the expansion will see the return of Tasha Yar’s daughter, Sela, and allow players to take on the Tholian threat.