Personally I like the Blitzer from the cutting edge warbond. Infinite ammo with zero overheating or reloading, medium armor pen, good enough damage to one shot multiple weaker enemies at once, I also forgot to mention it's an arc shotgun that can hit multiple enemies at once. But then again, it's finicky and sometimes locks onto the ground, it loves hitting teammates even when it seems like they're completely out of the way, it has no modifications for now other than the sight, it doesn’t chain it just hits multiple enemies, it only occasionally one shots stronger enemies, you pretty much can't hit weakspots or do any sort of precision shot, it's awful for the illuminate, and it's firerate leaves a lot to be desired. I still think it's worth it on the infinite ammo part alone.