When describing something as "rattiest", you may be referring to its worst or shabbiest condition. However, if you wish to explore alternatives to express this idea, there are several synonyms available. For instance, you might consider using the term "most dilapidated" to highlight the object's decay or disrepair. Additionally, the word "shoddiest" refers to something of very poor quality. Alternatively, you could opt for "grimiest" to emphasize a sense of dirtiness or filth. Lastly, the term "seamiest" can be employed to describe something as disreputable or sordid. These alternatives allow you to convey the notion of "rattiest" in a variety of nuanced ways.