Omega Games — S.L. Viehl

Now the intrepid surgeon uncovers psychological horrors even she can't cure....

After regaining her memories and saving the reptilian Hsktskt from a devastating plague, Dr. Cherijo Torin faces a different kind of epidemic: a mysterious black crystal spreading like cancer throughout the galaxy. A mercenary claiming to have information on the crystal's origins leads Cherijo and her husband, Duncan Reever, to the planet Trellus, but then leaves them marooned there.

Trellus is a world under quarantine. Its colonists exhibit excessive paranoia and anger, and take out their frustrations in simulated combat against battle drones in the Omega. Dome. But someone--or something---is killing victims outside the arena, leaving only their skin behind. Cherijo believes the black crystal infection, is responsible for this horror...and that someone deliberately triggered the outbreak.