Diablo III: Reaper of Souls

Doing levels 61-69 is a pain in the ass indeed, I dread doing them on my WD and Wiz now that I've finally managed to get my barb good damage and toughness (700k and 5,4m).

I had to change my whole skill build to fight Uzrael, got loads of cooldowns with stuns and Frenzy/Smite and would just run to his back when he used the flamethrower.

I only have like 260k and 3.0m on my Wizard and the game is still significantly better than it was before I was 70. The first rare that dropped for each armor/weapon type when I hit 70 was MASSIVELY better than everything I had, because everything I had was 66, or worse, 61. Right now the gear droppings are 60, 61, 66, and 70. There doesn't seem to be anything in between at all, it's awful.

Uzrael wasn't so bad for me on Wizard that I had to change my build, but that's mostly because I used Frost Familiar at the time which often freezes bosses in the middle of a dangerous attack which then cancels it when they unfreeze. I think the hardest part about his battle is that after he hits like 25% the battlefield turns into a maze of flaming death. I would lose half my health walking through it because I was trapped and would die otherwise.