Just had my other half ranting at me down the phone because of "Freezing Nightmarish Waller" mobs.
Now, I'm currently downloading Diablo 3. She's approaching 55 on her Monk and is working her way through the penultimate difficulty, so I've got all of this to look forward to.
I looked slightly further down this subforum to see a guy with an imgur link to him being dead and two mobs targetted: Bradshaw the Behemoth with Waller, Fast, Avenger and Frozen, and Jacobs the Gigantic with Health Link, Electrified, Fast and Fire Chains.
Anyone want to chime in with their worst modifier combinations and class?