He was definitely a leap up in difficulty, especially compared to Kilrogg who was a big joke. People were even scaring us on forums how this would be a 300 wipe boss.
We had something like 100 wipes before we started to get a hang on the boss, but once we got the coordination part somewhat down, we started making (somewhat) steady progress.
He was extremely difficult when undergeared, required a ton of coordination and patience.
There are also a good few bugs etc. that have been fixed since then, like pools spawning under people who have the debuff and are going down/increased digest time/immunities not spawning pools
The biggest nerf to that boss was people getting gear easily, almost 1 phasing the boss is a godsend as one of the harder sections was surviving during the 3rd normal phase with such little room left due to pools, meaning they must be dropped closer and closer to the group which means increased damage each time unless the person the debuff was on had an immunity and was still able to drop theirs near a wall.
As mentioned though, rings changed this entire instance, not having them is a huge deal in terms of difficulty for multiple reasons on some of the more difficult encounters such as mannoroth, archimonde and tyrant (this fight becomes a timing nightmare until you get it down with people getting more and more gear and upgraded rings, we just yolo it now), they also make xhulhorac even faster than he already was pre rings.
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