What is your favourite kindle unlimited series

I'm looking for some good series recommendations which are on kindle unlimited. I've come across some great sounding series on here but lots of them aren't on there yet and I'm wanting to try to read as many as I can while on a free trial. I've just finished reading the villains and virtues series and loved that alongside throne of glass (red before kindle unlimited) and lady of darkness series so anything similar to thoes would be amazing ❤️

Edit: just want to say thank you for all the recommendations! There are so many and I can't wait to start readung them 😊