Xanthos underwent a series of modifications during the Fall 2003 through Spring 2004 in preparation for the expedition to Greece. We have stopped the classification system using letters and now refer to this platform as the Odyssey IIx class. Modifications included: Bluefin 2kWh battery pack, single sphere configuration, 1.3 megapixel digital camera, 600kHz sidescan sonar, dropweight, and forward-look scanning-sonar. Her mission log so far includes the trips to MBARI, FAU, and expeditions to Kythera, Greece and the Fisheries Survey