Light citrus with berry. Crisp and refreshing sparkling summer flavors to take you back to those long hot summers! Monster Energy Ultra Red, sugar-free. Ultra has a refreshing taste and doesn't taste like traditional energy drinks and still has the full Monster energy blend. - Monster Ultra's lighter tasting flavour profile is a less sweet, sparkling energy drink that delivers refreshment, with 160mgs of Caffeine. Monster Energy Ultra is great for any occasion.