If something goes off the chart, it far exceeds the normal standards, good or bad, for something.
Uncharted waters
If you're in uncharted waters, you are in a situation that is unfamiliar to you, that you have no experience of and don't know what might happen. ('Unchartered waters' is an incorrect form that is a common mistake.)
An hart idiom dictionary is a great resource for writers, students, and anyone looking to expand their vocabulary. It contains a list of words with similar meanings with hart, allowing users to choose the best word for their specific context.
Kamus kata-kata serupa, kata-kata yang berbeda, Sinonim, Idiom untuk Idiom hart