Knock, Knock, Knock on Wood (10 player)

Or maybe it and it's two related achievements are just a reference to the famous saying "knock on wood" to prevent yourself from being "jinxed"? Not everything is a freakin' song reference.

After a few hours my guild was able to down this achievement. I will provide as much information to the best of my abilitiy.

Our setup:
2 Warrior Tanks
3 Melee DPS (1 Blood DK, 1 Unholy DK, 1 Combat Rogue)
2 Ranged DPS (1 Shadow Priest, 1 Survival Hunter)
3 Healers (2 Resto Shaman, 1 Discipline Priest)

First off, if you leave all 3 Elders alive, when you aggro Freya and the fight begins, all 3 of them will be banished, and will each give a buff to Freya:

Brightleaf's Essence
Ironbranch's Essence
Stonebark's Essence

All of these buffs combined, Freya's Physical and magic damage are both increased by 50% of normal, and the physical and magic damage of her allies are also increased by 50% of normal.

In addition, each Elder allows Freya to use extra abilities, which are:

Ground Tremor - Inflicts ~9k damage to all raid members and interrupts spellcasting for 8 seconds. Similar to Flame Vents from the Ignis fights, casters must stop casting when she is using this ability.

Iron Roots - Used on a random target every ~20 seconds. Deals around 8k damage every 2 seconds and immobilizes them. The roots themselves are targettable and have around 18k health. They must be DPSed down ASAP. EDIT: As of Patch 3.2, these roots can be removed from any ability that removes movement impairing effects. That includes Hand of Freedom, Blink, Cloak of Shadows, Shapeshifting. It would probably be best to have two Paladins using a Hand of Freedom rotation on those who get rooted. This alone makes this hard mode that much easier!

Solar Flare - Similar to fightning the Elder on his own, Beams will randomly appear every ~20 seconds. Those standing in the beam will take a DOT, dealing roughly ~4k damage per tick. The beam will also explode after some time, dealing damage to everyone sitting in it. Obviously, you need to make sure to stay out of these.

All the while, Freya will be constantly using Sunbeam

With all of these abilities, and the adds abilities, this makes the fight EXTREMELY healing intensive. Your healers need to be well geared, flasked, and food buffed for each attempt.

Now that I've described the abilities, I'll briefly describe the adds. They are the same as if dealing with Freya normally.

Ancient Conservator - As usual, you need to stand under the mushrooms to perform any abilities. He will cast Nature's Fury on random raid members, causing them to take ~4k damage per tick, and dealing damage to anyone around them. The affected raid member must get away from others ASAP, because healers will already be dealing with a lot of other issues. Other than that, this add is nothing special, and is the easiest one to deal with.

Elemental Adds - Spawns the Snaplasher, Storm Lasher, and the Ancient Water Spirit. We had 5 DPS, 2 ranged and 3 melee. How we did this is that all DPS started on the Snaplasher until he was at 40%. That way the movement debuff was applied, and thus the tank could kite it. Then, melee switched to the Storm Lasher, while ranged got on the Ancient Water Spirit. After that, we judged what we needed to DPS down faster, and killed them all at the same time. NOTE! The Stormbolt used by the Storm Lasher MUST be interrupted. With all the other damage going around, it's important that this one does not get added in either.

Detonating Lashers - These are the hardest adds and are simply a pain in the ass. Twelve of these spawns, and, as the name implies, they cast Detonate when they blow up, dealing roughly ~7k damage to anyone near it. This was the hardest part of the fight, and it's really up to your raid to decide how to deal with it, but here's what we did: We all gathered up on Freya's feet so the Lashers would be together, and we AoEd them down to ~20%. After that, a hunter dropped a trap about 10 yards away. Our warrior tank AoE taunted, and dragged them to the frost trap, and after the AoE taunt went away, he shockwave stunned them. During this time, AoE the mobs, and the warrior tank used Shield Wall to survive the Detonates. We had two warrior tanks, so the second time the lashers came up, they switched and perform the opposite roles. Overall, this add phase is EXTREMLY healing intensive, and if 1-2 people die and you have no battle rezzes, it's pretty much a wipe as you'll fall behind in the next add phases.

Phase 2 - After the 150 stacks of Attuned to Nature are gone, we found it best for the entire raid to be stacked up on Freya. She will always use her Iron Roots ability about ~5 seconds before she puts the exploding roots on the ground. Thus, it's best to destroy the Iron Roots, and then kite the boss away from the exploding roots. Rinse and repeat, the easiest part of the fight! Just stay mindful of the beams, and keep everyone topped off.

Good luck everyone!

EDIT: I heard that this hard mode in 10 man was significantly stealth nerfed, in that the health of both the adds and the boss were severely reduced. I don't have any additional information so I am not able to confirmed since my guild did this before this supposed stealth nerf, if anyone can provide information please do so. Thanks

You may be new to wowhead, so I will help to inform you. If you are going to tell us that you killed the boss, it's best to back it up with some information or tips that will help other groups beat it as well. Otherwise, it will just seem like you are trying to show off. And if that's the case, it's probably best that you go to a website called www.thottbot.com