yeah I think the same .. I killed two times before this and I think the same, they made it a lot more diffcult. I think that it does a lot more damage. With a friend we already failed twice killing it, and we had to retreat to fight another day. Previously with bonemass, fire resistant potion, you could tank it and kill it in a breeze. Previously it was too easy, now it's too difficult.
(Also before it didn't had the lava/blast attack, this was added before H&H but also noticed that)