There are many synonyms for the phrase "in full gallop," which refers to moving at a very fast pace. One option is "at breakneck speed," which suggests that one is moving so quickly that they are in danger of injuring themselves. Another option is "at a frenzied pace," which implies a wild and chaotic energy. "At a sprint" is another possibility, which evokes the image of someone running as fast as they can. Finally, "at top speed" is a simple and straightforward option that accurately conveys the idea of moving as fast as possible. Whatever the choice of phrasing, it's clear that "in full gallop" is a powerful metaphor for speed and intensity.