Stood outside casting Tornado over and over while COOP partner angrily made dinner. Gotta be careful as the Necro gunk gets in the walls if you let them use it.
There's a couple of fights which get the "Why on earth is this here?" badge, which in my book is 'Defending The Lady Vengeance', 'Blobbos On The Platform: The Trial of Hardware'*, and 'Realistic Simulation Of Dealing With Government Institutions: Fire Level'; which I'm glad the devs saved for last to really drive home the point that you're only having fun because they let you.
Seriously though make their respawn distance shorter and make it so the need a certain amount of tiles on fire to do just that. Little buggers respawn on top of single tiles that are hidden in the geometry. An encounter shouldn't by virtue of it working as intended seem like it's glitched.
(* 'Blobwalk Empire' was copyright claimed.)