This is what I am currently running with a Legendary Class Mod. I run with a Plump Kerblaster, DP Unkempt Harold, Tumtum Cobra, Pertinent Norfleet, 25% Explosive relic (looking for a better one) and a Deadly Bloom shield. This setup will melt faces all day long. The Harold is a bit OP in this setup, so I typically only switch to it when I am getting overwhelmed and only to dig myself out. Otherwise I stick with the Kerblaster as my main gun, but it is dangerous to use as you can easily kill yourself with it if you aren't careful.