I was there in 2018! I made a homage game to Juan, Juan Saga.
Something really important that I learned is that is really not ideal to join two game jams where one ends within a weekend and the other within a month...you will end up with people judging a work that's only 48h of production while expecting a while month put in work on it.
I participated in 2019 with When Boids Attack. It was one of my first 3D games made with Godot. So, yeah, I learned a ton! I guess the biggest take away is that when you limit movement to a single plane, 3D is just as easy as 2D.
