I am a big fan of Ninjago, Gravity Falls, and Undertale. In that order chronologically. 
 It's really cool seeing things people have made for these fandoms, even if I was technically not present at their peak. I joined Gravity Falls coincidentally at the same time as the Book of Bill came out last year. Same with Undertale, where I had heard about the game for a while but only played it for the first time this August. (2025) That just so happened to be exactly one month before the 10th anniversary. This means that some things are lost "forever," and it's sad like canon underswap. But through the power of the internet, some things can be saved. I may act like I've been here the whole time and know everything there is to know, but I am quite new and still discovering new aus!

Ninjago doesn't have many aus, but my favorite character is Kai
My favorite GF AU is Zero Gravity Falls by emberthestorian.  My favorite character is Stan
My favorite Undertale au is Underswap, and my favorite character is Papyrus (for all aus)

I can and will rant about EVERYTHING. (as seen above) I have also watched The Owl House, but never got into the fandom.  I have also read Wings of Fire and PJO + others, but I also never got into those fandoms either.

I never thought I'd have to stress about the character count when writing this, but somehow I am with 1404/2000. 
(It's the paragraph, isn't it?)(;;;・_・)