Actually, it occurs to me that there is a tidy comparison to make, encounter-to-encounter. It’s a single data point, so it doesn’t answer everything, but it should serve as a decent illustration of the point.
Slothasor is Grobbulus. Grob was a boss in Naxxramas, the first raid of WLK (the second expansion), which was on the easy side, as it was designed to get people back into raiding after the end-of-expac downtime, and to introduce new raiders to the concept. That said, Grob was in the Plague Wing, after Patchwerk and before Gluth and Thaddeus, which I think was considered one of the tougher wings, so relatively speaking it was harder than most of the other bosses in the same raid.
Note that this being the first raid of the second expac, this is going back about 8 years, so my memory of the encounter is apt to be a bit hazy, and there will be a lot of “iirc” here.
Grob was a gigantic, fleshy science-experiment monster man with machine parts and a nozzle hand. He was in a big, rectangular room with a few alcoves, and a ramp at the far side, which was either inaccessible when he was alive or else messed with the fight if the person with aggro ran up it.
The standard strategy was for the main tank (MT) to kite Grob around the room by backpedaling, while melee followed on the boss’ heels. I seem to recall that the boss had leashing issues, perhaps due to multiple attacks or his slow AA speed, but in any case it meant he would stagger a lot and sometimes would turn and spew green juice at the melee instead of the tank, so you had to be on your toes.
Throughout the fight, one or two people would periodically get infected with a bomb. You had a few seconds to run back the way you came and drop the bomb at the edge of the path. It would leave an expanding circle of poison that would eventually dissipate (or maybe they didn’t disappear and this was the soft enrage mechanic). (Some groups dropped in the center of the room, but usually that was where you had your healers stand, so it was easier for them if you had the sense to make it to the edge.)
There were also adds that would spawn — oozes — though I don’t recall the triggering event — probably something the boss did. The oozes would aggro onto the healers or perhaps just track toward the boss. In either event, the off-tank(s) (OT) would probably have to pick them up — from range, if I recall, because I think they did a bunch of damage if you were in melee range — and ranged dps had to burn them down. Maybe people also snared them.
There was some other mechanic to the oozes that escapes me. Maybe if multiple ones got together they joined and became a big problem, or maybe that was a different fight entirely.
I seem to recall disliking the fight and it taking a while, which probably meant that Grob had the special ability Damage Sponge, like most of the Plague Wing mobs.
By comparison, Slothasor’s room is filled with poison and interactive mushrooms. You are more or less required to kite, rather than figuring out the strategy. One person acts as MT and kites while everyone else sits on his backside. You still have to watch out for the spew (flame breath) but it’s not buggy (outside of sometimes not rendering).
You get a bomb debuff that drops a poison circle, but you have a special action that allows you to drop it, though there is also a timer (right?) (the Grob one may have been cleansed by healers, but I think it was just on a timer).
The adds can be a pain on Sloth, too, though you can manage their numbers with pulls and cleaving/epi. Eventually, they become numerous and more difficult, functioning as the soft enrage. You will have one person transformed, a feature not found in the WoW encounter, though you could argue that this makes a special-case OT.
Sloth has the shake and condis abound, which you can try to avoid, or can dedicate some attention to removing, kind of like a WoW healer, at the cost of dps, like WoW raid composition decisions.
Notably, Sloth has a very low dps requirement; it’s all about the mechanics. I’d say there’s more personal responsibility in Sloth, but there’s also rubbing downstates. Because all GW2 encounters have to be tuned at a single gear level, Sloth’s low dps requirement makes it a cinch once you get the dance down, much like a WoW encounter once you out-gear it. Sloth can be fun, though I don’t like to pug it. Grob was a chore, but that was probably because our guild was pretty experienced and Naxx wasn’t much of a challenge. Maybe this helps compare the two.
