If you get a fusion with piercing rounds it demolishes crowds of thrall in the pit. I also made this post before I knew of the 100% upgrade to shotty damage in pve so yes shotguns work great too
English
-
I was talking about icebreaker, on abyss you can use it hip fire and it just blows up everything it kills,these explosions make stuff that was killed by them blow up as well so icebreaker literally -blam!-s up your frame rate with this