Y'all sleeping on the Rotgland Lobber!
After dying numerous times in Biome 3, I finally decided to try the Rotgland Lobber. I found one with Explosive Rot, and along with the Adrenaline Damage Boost artifact, it made VERY short work of anything I came across in Biome 3. The crawling self-destruct guys I could take out in 2 hits, just about everything else (INCLUDING THE DAMN DRONES!) was a 1 shot! It helped that I also had "Resinous Shield" so I could take a hit now and then and not lose my adrenaline level and damage multiplier.
It also made short work of Nemesis at the end, particularly before I lost my adrenaline level...took out most of the 1st phase before getting hit. I had been REALLY struggling with this guy with the carbine and hollowseeker.
Yes, you have to get used to it "lobbing" over long distances, and yes, the fire rate CAN be a little slow...but this thing is POWERFUL! Also, keep in mind, you do NOT have to fully charge it before firing! It can fire almost instantly, and, if you get the rhythm, you can overload VERY easily, shot after shot, which is VERY powerful if you also have the overload bolts! If you haven't tried a run with this gun, I would STRONGLY recommend you do!