Yeah the lack of music is with much regret, I was working on it to iron out bugs right up until I uploaded it and unfortunately the music just didnt have time.
Its pretty easy really, I got the model and animations from mixamo, take that into Godot and place it into a viewport, then set a sprite to show the viewport. The spawning bugs should stop after you kill 10, perhaps something went wrong :/
I was tempted to make the third one be a random selection each time but I also kind of liked the choice to skip, I was going to add a timer for the wildcard but didnt get a chance in the end but I thought that would be a nice way to shave down the time taken.