Head on through to Head Shot Headquarters. Head over to the right to start fighting all the Bandits that start appearing with some Surveyor Support. You will be dealing with Marauders, Blaster Nomads, Badass Maniacs, and Maniacs. Get through them and you have to face down a Super Badass Loader, Super Badass Marauder and a Badass Maniac. The final foe is a duo of the Black Queens. When you kill the first one it will break into at least 5 Spiderant Praetorian. Kill them and you will be done with this small area.
You will gain an optional objective to pick the Snow Onions if you head to the West and into Obliteration Station. There you will find a number of duos of Bone Heads 3.0 coming after you. Head deeper in (or to the West to the Garden of Murder and you will be facing more Maniacs. Likely they will have with some Surveyor Support as well. There will also be some EXP Loaders added in as well for you to deal with along side the Cannibal Rats. Defeat them all and continue to the South to make it into Decimation Destination.
Once in there you will encounter more Rabid Skags. They are followed by a Super Badass Slag Skag then 2 Digistructs of Doc Mercy with a Maniac Midget. This is followed up with a large wave of Marauders. Head on over to the South and then start up the stairs you find there when you are done with that group.
At the top of the stairs you have even more foes to deal with. There is a Emperor Spiderant and a Super Badass Surveyor Ver 2.0. Kill them and continue on through. This leads to The Colosseum of Laceration.
The Colosseum is near the end of the course. At this point this get hard as you will now be facing the Assassins from Southpaw Steam & Power. First is Assassin Reeth. Use cover and keep on the move to avoid his thrown axes and leap attacks.
Next is Assassin Wot. He will jump around and take cover against you. Return the favor and it should not be too hard to take him down. The problem is the addition of a SPD-TNK to the fight. This makes cover more vital to avoid the incoming barrages from the tank.
After him is Assassin Rouf and Assassin Oney. This Rat-type, Rouf, enemy will be running around and attacking with his shotgun. It helps to keep him as a distance as much as possible (or just charge in there) to cut the damage from him. He is very fast so keep on the move. This is twice as important as Oney is added in and will charge you when he has a clear line of sight. Head into the Area of Anguish after you have finished them all off.
In this area you will face a SPR-TNK, Surveyors and Horned Skags, a Slagged Centurion Spiderant. Kill them and head toward the farther end of the area. You will encounter more Arbalest Spiderants, Marauders and EXP Loaders.
When you defeated all of them then you face something big: 2 Saturn v2.0. They the much stronger and tougher version of the Boss from the remains of Fyrestone. Keep in shelter and unlock using Corrosive-type damage. It shouldn't be as bad to deal with overall with those things in mind, just lengthy. After the fight, the door will open to the next section. Head on through to Cannibal Canyon
In Cannibal Canyon you will face Cannibal Rats, a Constructor Ver 3.0, and a SGT Loader. After them come Marauders and more SGT Loaders. They are followed by an Ultimate Badass Loader and Badass Marauder with a little 1 Surveyor supporting. Kill them and you need to press on. There is more yet to do.
The second part of the fight here has you going against a Surveyor, a Super Badass Slag Skag, Super Badass Loaderand a Badass Marauder. Defeat them and Tannis will announce you are near the end of the course and she will bring out the biggest challenge yet. Head on up the slope to the elevator that takes you to the Tower of Torment.
At the top of the elevator you will start the round by fighting the final boss of the run: 010011110100110101000111010101110101010001001000. Remember, this is one massive tank, like the ones you encounter earlier. Take advantage of cover to avoid the worst of the incoming damage. This foe is the one of the few that has a chance to drop Pearlescent Weapons