Answer:a dramatic change of events
Explanation:
A colon suggests that there will be a list that will follow it. Using the words 'such as', 'for example', and 'including' in a sentence also directs the attention of the reader to a list. It will be redundant to use a colon after the word 'including' in a sentence.
Percy is happy to see his mother again after being in the boarding school. However, he hates his stepfather.