The magician’s tricks were so great that everyone was amazed or astonished.
To understand what the word or phrase is that completes the sentence, we need to consider the context. Given that it is about a magician's tricks being "great," we can infer that the missing word or phrase could be "amazed," "astounded," or "awestruck." These words convey the idea that everyone was extremely impressed and in awe of the magician's tricks.
