The fat dragon is what really landed the movie for me. That? That was a DM decision, based on the players and the DM being memelords. Straight from the tabletop.
It really just demonstrated that the whole movie is a DnD campaign (agglomerate homebrew) with extremely high production value, and I LOVED EVERY SECOND OF IT.
The fat dragon, Themberchaud, is actually a canon obese dragon. He’s in the Out of the Abyss module and some others.
Huh, TIL.
Still, without knowing that, it looked exactly like the kind of collective meme the table would come up with and beg the DM to add.