Performance Energy Drink. Sugar Free • Zero Calories. Vitamin Fortified. All Natural Flavors and Colors. Official Energy Drink UFC Ultimate Fighting Championship. Carbonated. Xyience means extreme science. At Xyience we seek to power the human spirit and fuel peak performance. Xenergy is a blend of Zen and Energy...a great tasting performance energy drink that fuels champions. Whether you are training for a title or trying to reach your personal best we've got you covered with all natural flavors vitamins and nutrients. We skip the sugar and calories giving you the Power To Win.