Having never gotten to do an old school 4H fight, I was determined to create from scratch LOKI's plan for Heroic: And They Would All Go Down Together. And with achieving it on our second try, I would consider it a success!
To get "And They Would All Go Down Together", you must kill all four Horsemen within 15 seconds of each other. The key to this achievement is control. Not just over damage, but over marks, and incoming damage.
Most guilds (ourselves included), on non-achievement kills, gain control by zerging Thane. Once he is dead, no horsemen have to move from their spot, the raid just shifts around to avoid stacking marks, and it's pretty hard to lose. This is obviously not a viable method for gaining control for the achievement.
When we started this encounter way back when, we first attempted doing it "as intended", and having the Thane and Baron tanks meet in the middle and taunt off each other, then go back to their corners. Where this failed us, was that we'd frequently have people get marked by both during that switch, get out of sync on marks, ect. So we've added some more tanking, and made it failproof.
The first thing, is to form six "tank" + Healer pairs (Front and Back Groups 1-3). For the front, you'll need an actual physical damage tank (Warrior, Paladin, Druid, DK). For the back, any high HP, magic resistant / self healing hybrid class will do (Deathknights & Arcane Mages are nice, but certainly not necessary). Any type of healer will do for each group.
Then split DPS into four, fairly even groups. All melee must be in DPS groups One and Two, and hunters need to be in the back (as they can't DPS from point blank). Put short-ranged casters in the front (Shadow Priests, Elemental Shamans).
Role by role, here is how the fight plays out.
Front Group 1 (FG1): Start on Thane. When the next tank (FG3) relieves you of duty, wait for the next meteor cast, then go to Baron. When next tank (FG3) relieves you again, go to the center platform. When the Thane Tank (now FG2) has two to three marks and meteor has been cast recently (and your Thane marks are gone), then go relieve him. Repeat.
Front Group 2 (FG2): Start on Baron - otherwise follow the same rotation as FG1, but following/relieving FG3.
Front Group 3 (FG3): Start on Center platform - otherwise follow the same rotation as FG1, but following/relieving FG2.
None of the horsemen move, and healers are always able to stand completely still while healing their assigned targets (both healer and tank can get into position before they start needing to tank / heal. This is Control. You'll see a similar theme in the back, but with extra empathesis on distance from boss.
Back Group 1 (BG1): Start on Zeleik, with your tank about ten yards away, and your healer beyond that (ten-fifteen yards away). When the next tank (BG3) relieves you of duty by stepping in front of you slightly, head to Blaumeux. Relieve that tank (BG2) by stepping slightly in front of him (and making sure you cast some spell on her). When next tank (BG3) relieves you again, go to the center platform. When the Zeleik Tank (now BG2) has two to three marks (and your Blaumeux marks are gone), go relieve him. Repeat.
Back Group 2 (BG2): Start on Baron - otherwise follow the same rotation as BG1, but following/relieving BG3.
Back Group 3 (BG3): Start on Center platform - otherwise follow the same rotation as BG1, but following/relieving BG2.
DPS Groups 1 And 2: You have the slightly more complicated job of the DPS. Whichever group is on Thane stays super-bunched-up on him, until relieved by the other. And when you move away from him, do so in a tight group. These are all precautions so that you don't get killed by Meteor (or let the tank+healer group thats on him get hit by themselves). When you move to Baron, stay there and DPS (using short cooldowns, since you'll get to spend less time on him) until Thane marks fall off, then head back.
DPS Groups 3 And 4: Stay well behind the tank/healer combo that is on whichever mob your on. When you get three marks, switch (you'll get out of sync as a whole, but thats OK). Don't be afraid to spend a little extra time on the higher HP of the two back mobs, or a little less on the lower. (but no less then you need to drop the old mark)
The Actual Killing of Them: Baron is likely to be your highest health target the whole fight. Thats OK. DPS all mobs as strong as you'd like down to 10%, then stop using anything with a DoT. Continue Auto-attacking down to 5%, then hold on that mob. When they are all sub 5%, tell people to get into their final position (read as, don't move for the rest of the fight), and blow heroism. Don't get more then 2% ahead of other groups, continue to have control. When one dies, it becomes a free-for-all burn fest.
Profit. Together, this all can seem pretty complicated. But when you look at each groups individual responsibility, its not that hard. Really, the most difficult & time consuming thing is for the Raid Leader to organize the groups correctly (this is what took us the one attempt before the kill), and then just let things go. (Oh, and as a note, everyone should have DBM's option to show health for all four horsemen enabled).
At the time I'm writing this, only 553 US guilds have done this achievment. You could be 554! Give it a spin, and you'll find that the patience and control gained/enforced as a result of this achievement feels pretty good, and will serve your guild well in future raids.
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