Hunter solo - Durendil vs Echo of Neltharion Mythic
This may look easy now but the reason I waited for the 11.0.5 is because, without AoE and with lower gear, I couldn't make the dps checks.
In phase 1, you need to phase the boss before you run out of room. However, as a hunter, I could use my pet to stack fire on top of fire, gaining time.
In phase 2, I had to make sure to get the boss to 35% before phasing, in order to beat the enrage in phase 3.
In phase 3, you have a limited time to kill him before he chain casts his AoE, but now that the adds died to my AoE it wasn't an issue.