In this next tutorial, you're going to want to make sure you have plenty of time on your hands. That's because this boss battle is pretty long. You'll be going one on one with the sand boss Stygian. He's a giant, ugly worm that takes some time to defeat. On top of him, you;ll have to battle a bunch of enemies who are on foot.
If you're prepared for battle and have the time to spare, check out the tutorial and good luck. Oh, and if you have the Mercy gun, it will go by much faster. Good luck and enjoy!