Well, I really liked the fanfic 'Young Justice: Against Doomsday'. It has a unique take on how the team strategizes to take on Doomsday. The story shows the growth of the characters as they are forced to come up with new ways to fight an enemy as powerful as Doomsday. It's full of unexpected twists and turns, like when one of the minor characters steps up in a big way to help in the battle. It's a really engaging read for any Young Justice fan.
There's a fanfiction called 'Doomsday's Dawn in Young Justice'. In this story, Doomsday is not just a mindless brute but has some complex motives. It delves deep into the possible origin of Doomsday in the Young Justice universe and how it affects the relationships between the characters. For example, Superboy's struggle with his identity becomes even more pronounced as he faces Doomsday. The author also does a great job of building up the suspense throughout the story.
One great Young Justice Doomsday fanfiction is 'Surviving Doomsday'. It shows how the team in Young Justice copes with the arrival of Doomsday. The characters are well - written and it has some really intense action scenes.