Ok, so a good way of defeating the devourer is to fly really high into the sky, making the worm follow you as usual. Next, you fall to the side very quickly, so quick that you outrun the worm, and then you go under the worm as it approaches the ground. While you run under the worm, damage the head and the tail by flying back up while the worm tries to go up again. Repeat this process and be weary of projectiles.
*EDIT* I haven't fought the updated worm before, so take this advice with a pinch of salt. I've only fought the worm when his falling was extremely slow, which led me to my inevitable win. Chippy's Couch followed my advice, and killed the devourer many times.
He didn't acknowledge me though ;-;