border said:
I'll give it a try. Your post reminded me to ask because I recently got rocked trying to tank a Heroic Violet Hold run for the first time. People here said it was one of the easiest Heroics, but damn if you fuck up and wipe you have to face all those waves of enemies again.
I attempted to learn the Heroics by pugging with my warlock, but it's pretty hard to find groups as DPS.
VH is easy to tank as far as waves go, but it varies wildly depending upon which bosses you get. Zuramat is almost always a wipe because most people don't remember Jin'do, Xevozz can be tough until you realize he's easy as fuck to kite if you just pull him up the ramp from where he spawns and kite him
slowly because the enrage range for his spawned adds is really short, moreso than you would think by looking at them. Everyone else is pretty simple, although I've only gotten Ichoron on normal. But he's basically the slime boss from AQ40 except you don't have to freeze him.
Nearly every other heroic is literally the same shit as normal, with possibly one extra move that won't even come close to wiping your group. I actually think UP is one of the harder heroics now but it's entirely dps dependant. If you have shit dps, good luck getting past that asshole on his blue proto drake. If you have good dps, then the instance is pretty easy, mainly because any naxx10-ready tank can grab 1/3 of the adds on the way to the door and the rest immediately at the spawn.
H-Nexus is a popular one because it's easy and 5 emblems, and keep in mind for the achievement on the last boss you pretty much just jump in place as melee. No real need to run around kiting her, and that includes the tank. H-AN is a gear check for the first boss for tank and healer, so if you aren't def capped and 22k+ unbuffed HP, don't even bother. However, once you can take the first boss easily, the entire dungeon is as much of a joke as it is on normal, typically beatable in less than 30 minutes. Still have yet to get the achievement for him, but good DPS makes the achievements for Anub'arak and Hadronox simple.
H-Old Kingdom has an extra boss off to the side of the cultist area with Jedoga Shadowseeker. This extra boss is easy to beat as long as people aren't retarded, which means 2/3 of your DPS will keep debuffed and do 0 damage the whole fight. Basically it's a mushroom boss, you hit him with single target tank shit, and he will debuff you so you lose your defense and a ton of damage dealt (but not healing) and the only way to break it is to be near one of his healthy mushroom spawns when you kill it. It's kind of like the reverse Loatheb, I guess, in that you break his debuff by killing crap that he spawns, but he doesn't spawn them on waves like that. I mean technically he does, but it's a shitload of mushrooms, both good and bad, and you kill the good ones and ignore the bad ones. V-targeting is all you need for that one because the bad ones are poison mushrooms and the good ones are healthy mushrooms. Anyway, yeah, you break those and you lose his debuff, and go back to killing him normally. That's literally the only thing the dude does that's special.
I can't even remember what's really different about any other heroics. Oh wait, Heroic Oculus has a second phase to the last boss. He banishes himself and summons orbs you have to fly around and avoid. Really simple stuff.
. And I love it. Having that option is amazing. But I could use at least one more for a BM spec for PvE and maybe even a fourth for an 3rd dps spec for PVE that forgoes what works out to be about 4% BA damage for the extra 6 yards of range on some of these fight later in Ulduar. 
