The phrase "ass-kicking" is a slang term that is often used to describe something that is extremely impressive or powerful. However, there are several other synonyms that can be used to describe the same thing. These include terms such as "badass," "kickass," "awesome," "amazing," "epic," "phenomenal," and "incredible." All of these phrases can be used to describe something that is really impressive and powerful, whether it is a person, an action, or an event. So, if you are looking for a phrase to describe something that is truly amazing, there are plenty of options to choose from!