Talking to Chase Hasbrouck about it today, I realized that to him, Spine is a completely different fight. Tanking heroic Spine, you're a freaking rock star. You do more damage, you get to deal with escalating difficulty, and by the end, the fate of the fight is as much in your hands as it is in the hands of the DPS and healers. If the tanks go down, it's basically a wipe. But for everyone else, Spine can feel like seven minutes of the same exact thing followed by two minutes of hectic, frantic repetition, hoping you'll get to the end.
What you do and where you do it
It's hard to realize that your memories of your favorite fights can be skewed by what you did during them. Vaelastrasz the Corrupt was one of my favorite fights as a tank because of the Essence of the Red buff and the Burning Adrenaline debuff. You got endless rage and the boss was almost in execute range! If you got lucky, you could just stand there in fire resist gear with a two-handed weapon and beat on him while every other tank blew up and died. Even if you were one of the tanks who blew up and died yourself, it was a fun ride getting there.
I hated the suppression room and the Broodlord fight, however. I still do. Again, based entirely on what I got to do there, which is run slowly and try and keep every whelp and add on me. Having to constantly run into the cubbyholes on the side of the room and kill them, then move fast before they respawned? Ugh. Hated it.
Boring for me, exciting for you
To use modern fights as an example, I hate Ultraxion because as a tank, all I do is constantly taunt and then port out of the encounter on Fading Light. It's a tedious mechanic. But when I DPSed it, I enjoyed a fight where the dang boss just stands still and lets me hit him.
Some fights are more fun for your role than others. A lot of healers I know still talk excitedly about Valithria Dreamwalker. As a tank, I had to run around picking up adds constantly, then watch them get ripped away by DPSers who would throw everything they had at them before I got more than a Shield Slam off. But for a healer, this was their rock star moment. Heck, even our prot pallies would throw a Lay on Hands on her. Back then, I was a draenei, and I used Gift of the Naaru on her on cooldown.
Sometimes class or role makes the difference
Being a blood DK was awesome on Chimaeron, and an enhancement shaman can absolutely destroy the universe on Yor'sahj. For people not playing these special classes/roles, it can often be hard or impossible to understand the appeal -- to those people, these fights can seem boring or not fun. It's a delicate balance, ultimately, and we often discover by trial and error which fights are best for which classes and for what reasons.
I really hate Morchok, for instance, again because as a tank, there's nothing for me to do really, and as a melee DPSer, I'm handicapped by no real ranged attack and no way to ignore that black crap and get more uptime on the boss. (Bosses on heroic.)
This is what makes evaluating boss fights so problematic for me. How do I compare Putricide as the guy tanking him versus the guy driving the abomination? Tanking heroic Lich King himself vs. tanking the adds and getting the disease stacked on them? I really hated tanking Cho'gall, but I loved the fight as DPS. And I never heal, so how do I rate a fight that I may personally love but which the healers curse up and down the walls? In the end, fight balance is subjective, based on where you were and what you were doing during it.
But heroic Spine of Deathwing is still awesome.
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