Jadzia Dax
by Evan Lorentz

At long last, a major character has come along to provide something no other "bridge crew" has -- SCIENCE. What's more, Jadzia Dax also has five great skills. Navigation (x2, no less) is increasingly important against Badlands strategies, or dilemmas like "Subspace Seaweed." Exobiology has become a vital skill against dilemmas like DNA Clues and Garak Has Some Issues. And at least one of the three "As" (Anthropology, Astrophysics, and Archaeology) is useful in the average Federation deck.

Combo:
Jadzia Dax + Cultural Observation + Hunt for DNA Program + Pegasus Search + Symbiont Diagnosis: Jadzia can contribute to more high-point missions than vitually any other personnel.