This dungeon comprises five boss fights:
The Lost Dwarves
Interrupt Defensive Bulwark coming out from Olaf, it provides a 75% damage reduction for the remaining of the Dwarves. It is important to note that during the entire duration of the Defensive Bulwark, Olaf does NOT cast any other spells nor auto-attacks.
Once the Dwarves reach low health, they will hop on Longboat Raid!, and fire Searing Cannonfire at every alive member of your team at their current location. You must be stacked at this point and move slowly together to "save" space as the Searing Cannonfire will keep ongoing until the boss is defeated. On Mythic difficulty, the boss will gain an extra mechanic; after each blast of Searing Cannonfire it will leave Burning Pitch behind it which will last for 30 seconds.
Focusing on one boss at a time is going to be beneficial, as Hasty Rearming will increase the rate of which Searing Cannonfire is firing, the more Dwarves there are, the more frequently it will cast. This effect can snowball, especially on Mythic difficulty where Fiery Surge and Burning Pitch must be taken into account.
Use mitigation when Baelog is casting Wild Cleave. In addition, the ability "cleaves" any players in front of him within 10 yards, so it is important to to face him away from your party to avoid casualties.
Throughout the whole fight, you will also need to pay attention to Baelog's Heavy Arrow. It fires in a straight line (non interpretable), damaging the players and knocking them back upon inflicting damage. It always goes where you are facing the boss, keep it away from your party to avoid unnecessary deaths.
On Mythic difficulty, you will have to think about Fiery Surge, each time the boss fires Searing Cannonfire, the entire party will be damaged, this is going to be a good place to use your healing cooldowns.
Few seconds into the fight Bromach will cast Call of the Deep summoning Stonevault Geomancer and Stonevault Ambusher (the same mobs that you have previously fought to get to the boss). It is important to note that because of Stonevault Geomancer being a caster, they will stay far away while casting spells on you. The best way to deal with them is to line of sight so they can come close to the tank or use interrupt/knockback abilities so you can "lock" them on cast and make them move closer to you.
Occasionally, the boss will also cast Thundering Slam, move out of the ground effect as quickly as you can.
When Bromach casts Quaking Totem, you have to instantly shift your focus to it and kill it. While the Quaking Totem is active, the entire party will take Shocking Quake damage, so it is extremely important to nuke it quickly. Upon destroying the Quaking Totem, it will cause Tremor stunning all nearby Stonevault Troggs and increase their damage taken by 200% for 10 seconds.On Mythic difficulty, this effect is only limited to 8 yards, unlike Normal and Heroic, so make sure you kill the totem on top of Bromach and the Troggs.
On Mythic difficulty, stack the existing mobs under the Quaking Totem, as well as the Bromach itself, so as soon as you kill it, every NPC alive will be affected by Tremor, essentially speeding up the boss fight.
Top up your teammates when they get damaged by the Stonevault Troggs.
It's important to understand how Ancient Dynamo works. At the beginning of the fight, the boss will have 2 stacks of Inexorable, which gives her immunity to stun effects. Why is that important? Because later on, we must stun her with Resonating Orb (3 spawn at player locations) prior to letting the boss cast Titanic Empowerment.
Occasionally, Sentinel Talondras will cast Crushing Stomp, knocking players away, interrupting their casts and also dealing physical damage
to all of them. Stop your cast at the end to prevent being spell locked.
Avoid soaking any Resonating Orb, this will significantly increase the difficulty of the fight.
On Mythic difficulty, the boss gains Unrelenting, which stacks, making this boss have a "soft" enrage. You want to save your cooldowns and kill it as quickly as possible.
The boss will cast Titanic Empowerment once she reaches 100 energy, it is important for you to clear her remaining stacks of Inexorable with the Resonating Orb before she gets close to 100 energy, so later on you can stun her with the last Resonating Orb on the Titanic Empowerment cast, preventing her from empowering.
Use healer cooldowns when Earthen Shards bleed effect is going out (it will cast on random party member), this is a good time to suggest to your teammates to use their personal-defensive. There are several spells that can completely mitigate the Crushing Stomp effect, here are the most popular ways: Stoneform racial, Paladin's Blessing of Protection or any other immunity.
When you engage Emberon, he will cast Activate Keepers (you can't attack them until the boss is "phased"), each of them spawning a Purging Flames. It is extremely important to dodge them at all costs, they rotate slowly. If you want to pass through them, use an immunity or a heavy personal-defensive to survive (example can be Rogue's Cloak of Shadows, etc.). Here are the most important details about the fight:
Periodically, Emberon will cast Unstable Embers on a random player (on Mythic difficulty it targets all the players), it is extremely important to be spread and never overlap each other with the surrounding circle. This is a great place to use your personal-defensives.
The boss enters its "phase" once he reaches maximum energy. During the phase, he will have a Sacred Barrier aura, preventing you from damaging him (be careful not to stay in the middle where the boss is, because you risk being hit by Heat Engine). The phase will end once you defeat the 4 Keepers, but the tricky part here is every 3 seconds of the "phase", the boss will cast Fire Wave. You can assign each Keeper to a specific party-member so you can defeat them faster.
Purging Flames will be present during the intermission phase, needless to say that it will probably turn lethal if you cross it. Unless you have an immunity don't risk going through. Teleport effect will completely ignore the beams - Mage's Shimmer for example.
Aim the Searing Clap frontal away from your party members.
Be ready to dispel the Burning Heat damage-over-time effect immediately.
Chrono-Lord Deios is a straightforward boss fight with an "intermission." Periodically his energy will decay from 100 to 80-60-40-20-0 (5 ticks, 20 per each tick) upon which the Rewind Timeflow begins. Stay in all Temporal Zone before they disappear as this grants you 30% Haste for the remaining duration. When the boss reaches 100 energy, the Rewind Timeflow ends and so does the "intermission." Here is a more detailed breakdown of the fight:
Beware of Wing Buffet, as it will not only interrupt your cast, but it will knock you back, causing you to take physical damage. Make sure there is no Eternity Zone left behind you to avoid further damage.
Sand Breath must be tanked away from the group, as it is a frontal-cone ability that targets only you until the cast is finished.
On Mythic difficulty, the boss will cast Time Sink, the debuff goes on a random member of your party and upon dispelling, it will trigger Time Eruption. It's best to wait until the target is "safe" to be dispelled.
Use healing cooldowns when Rewind Timeflow begins, it will damage to everyone in your party every 1 sec for 12 sec.