He was level 32, and me (Lv.30 Psycho) and a friend (Lv.30 Gunzerker) couldn't kill him. I am level 35 now and barely managed to do it, with a pretty unorthodox strategy..
So I just run around until the first Sand Worm spawned, then killed it and waited about 15 seconds for the acid to spread. I then led Gee in to the center of the pool and ran in circles making him follow me and lowering his shield. If my health got low, I went in Badass Psycho mode to restore health, and ran around meleeing more Worms to refill health (while ignoring the new acid fountains.)
Once his shield broke, I pretty much started running in big circles around the outside perimeter trying to avoid Gee and all of the Worms as best as I could. Again, if my health got low, I would use my Buzz Axe Rampage once it was below 33% to refill it, then keep running in big circles, but now I was throwing axes at worms to refill health while Buzz Axe Rampage was still going on. Once it ran out, I would wait till health was below 33% again and rinse and repeat.
Since the acid fountains stack on top of each other, it eventually got to the point where when I came out of Buzz Axe Rampage, I would die before I could go back in to it, because it takes about two seconds to restore once it ends. When this happened, I would just kill a Worm in Fight For Your Life, which would restore my shields and give me enough time to activate Buzz Axe Rampage again.
So pretty much I ran in circles like a chicken with it's head cut off. I never even shot Gee once, although I did accidentally throw an axe at him, which hit for 68K damage LMAO! That was from 20 stacks of Salt in the Wound (+150% Melee Damage), plus my class mod (+33% Melee Damage, Silence the Voices +3 [+400% Melee Damage] and Empty the Rage +2 [+98% Melee Damage]), and in Badass Psycho Mutant mode (+100% Melee Damage), the throwing axe did like 68K damage.. That's an absurd amount of damage on only a level 35.. This class has gotten tremendously fun ever since unlocking Release the Beast.
Stop taking exactly what I'm saying and repeating it as if its exactly what I said because it is. -Cryptospuridium