The novels in my series are all something that I would consider different due to a few things. The first being the main characters actually do die. And they don't necessarily die and then the book ends. Sometimes they actually die pretty close to the start...
Although this happens I couldn't actually let them fully die and they do come back which has lead them to experience death just a few times...or maybe a few thousand times... But if they die they come back with another identity and sometimes have to ruin what they built in a previous 'life' which is all because of the magic they were born with allowing them to travel to different worlds and time periods and dimensions when asleep and integrate into the societies there.
Another thing that makes mine different is one is literally almost fully focused on pranks... The school literally has a full system with rules and everything that lets people prank whoever they want and not get in trouble unless caught in the act. They also tell which group they belonged to at graduation and all that happens is they get congratulated on their successful pranks. And I somehow made it that to save a kingdom a group of kids who excel in pranking people is what is needed to regain a relationship between them and another species that believe the kingdom attacked them. No clue how that works but it does somehow. Oh someone dies from the pranks too so that's fun.
Each of my books has at least one completely strange or ridiculous thing in them because why not. I don't even remember all the crazy stuff I did. Though I know I made a pet in one world that is basically just mashed potato somehow.
Secrecy and plot twists are also a big part of my books (whether part of my series or a stand alone) and almost all of them have some sort of magic system that I spent way too much time on...