Monster Energy Ultra is an energy drink that offers a refreshing citrus flavor with zero calories. It is designed to provide an energy boost to help individuals stay alert and focused throughout the day. The drink is marketed as a perfect blend of energy and taste, making it a popular choice for those seeking a quick pick-me-up. Some reviews mention that it has a good taste and provides a good energy boost, while others mention that it has a strong flavor and can cause jitters. Overall, Monster Energy Ultra is a popular choice for those looking for an energy boost, but it may not be suitable for everyone due to its strong flavor and potential side effects.