Mythic Kel’Thuzad Boss Guide

BY crzypck / August 22, 2021

Written and produced by Crzypck

Special thanks to our consultant: Tagzz

← Back to Guides

Mythic Changes

  • Stage 1
    • KT starts with 3 stacks of Necrotic Surge
    • This means you’ll start with 4 Glacial Spikes and 4 Oblivion’s Echo 
      • This still increases each subsequent Stage 1
      • Means lots more adds and lots more Spikes, making placement and planning more important
  • Remnant of KT
    • Gets new ability
    • Foul Winds
      • Pushes everyone back, away from center of the platform
    • Shadow Fissure
      • The swirlies now leave puddles on the ground after they explode
      • This means you’ll run out of room down in the phylactery after a certain period of time, and forces you to stay as a group and try to bait & consolidate the puddles
  • Stage 2 (top side during phylactery)
    • The bolts from the Banshee’s cast now freaking truck, and almost 1 shot
    • If you fail interrupts and 2-3 bolts get off you’ll have people die. This can never happen
    • Any adds that are still alive when KT reactivates, now deal 500% increased damage (up from 25% in heroic)(LOL)(this is bad)
  • Stage 3
    • Onslaught of the Damned now also spawns Frostbound Devoted adds

Strategy

  • Comp – 2 tanks, 4 heals, 14 DPS
  • Stage 1 (first time)
    • You’ll have 4 Glacial Spikes, and 4 Oblivion’s Echo, each time the abilities are cast
      • Put a marker near the front of the room, and drop all 4 Spikes on the marker. You’ll ignore these, and let them just naturally tick down and explode
      • Make sure you use 1-2 Healer CDs to keep the raid stable
    • All Oblivion Echo circles should be brought to the entrance of the room, and dropped stacked on top of each other
      • By doing this, you’ll make sure the small adds are always stacked up tightly when they spawn, making it far easier to deal with them
      • You’ll want to use things like Ring of Peace, knockbacks, Vortex, etc. Whatever keeps them near the front area and away from people
    • The downside to stacking the Echos like we recommend above, is that you won’t have them to interrupt tank adds. Oh well, interrupt them yourselves
      • Use an interrupt assignment WA if need be, you’ll want to interrupt as many casts as possible
    • Blow up the tank adds ASAP
    • Aside from just handling the mechanics, there’s one other very important part of Stage 1
      • Delay delay delay. Do not push the first Stage 2 until about 2:20 into the encounter
      • Get the boss to 4.5%, then hard stop all DPS
      • Sub 4.5%, the boss’s spell queuing stops and he just won’t cast at you
      • By doing this, you’ll give 2 and 3 minute CDs time to come back up, so you can use them at the start of the second Stage 1. This helps with spell queuing and getting through the later parts of the fight more quickly and reliably
  • Stage 2
    • You’ll want to send 4-5 DPS down with a healer into the Phylactery
      • Recommend these be the top single target DPS. 
      • 2-3 DPS should use their CDs to blast the add in the first Stage 2 
      • The remaining DPS in Phylactery should NOT use cds on the first Stage 2, and save for the 2nd Stage 2 Phylactery
      • You’ll need to feel this out a bit, and decide based on your raid team which CDs work best for each of the first 2 Phylactery burns
    • Inside the Phylactery, you’ll want the team down there to stay stacked tightly and move as a clump
      • The swirlies are targeted at random players in the Phylactery, so by staying grouped you can fully control where the puddles end up
      • Rotate around the Remnant’s platform, moving each time the swirlies appear
    • While that’s happening, the rest of the raid needs to deal with the adds
      • The Banshees are extremely dangerous. The bolts they shoot deal massive damage, near 1 shots
      • The initial cast is about 1.5 seconds, then it’s a channel
        • The first bolt shoots as soon as the 1.5s cast completes, with more bolts shooting throughout the channel
        • You want to interrupt the Banshee casts BEFORE the 1.5s completes. If you don’t, it’s likely someone dies
      • The abominations just have to be tanked. They truck, so tanks need to make sure they help keep themselves alive
        • Don’t get hit by the obvious green swirlies
    • The difficult part for Stage 2 is timing. You do not want the adds to ever respawn, and you don’t want adds alive when KT reactivates, so it’s vital you time everything properly
      • What we found was best, was to DPS the adds to below 20%, then chill
      • When the Remnant is within 10% of the target HP for the stage to end, call for DPS to go ham on the adds
        • Blast the adds, and the DPS in the Phylactery blast the Remnant
        • Ideally, the adds die about 5 seconds or so before the Remnant
        • Doing this will take a few attempts to get used to the exact timing for your raid’s DPS setup
  • Stage 1 (2nd & 3rd times)
    • The boss will start at 100 energy
    • The phase is pretty much scripted from this point on
    • About 15 seconds in, you’ll get tank adds
    • About 20 seconds in, you’ll get Oblivion Echos. There’s 5 in the 2nd Stage 1, 6 in the 3rd Stage 1
      • You should still bring all Oblivion Echo circles towards the entrance of the room, stacked up. This’ll keep the adds consolidated
    • About 30 seconds in, you’ll get Glacial Spikes. 5 in the 2nd Stage 1, 6 in the 3rd Stage 1
      • We recommend dropping 1 Spike off to the side and killing ASAP
      • The other 4 should be dropped on a pre-set location, and ignored
        • Let this group of 4 tick down naturally
        • You’ll need 1-2 healer CDs to survive the explosions and DoTs, so make sure you have them assigned
      • If you have 2 DR CDs available, you can actually get away with all 5 Spikes exploding at the same time
    • About 45 second in, you’ll get more tank adds
    • About 55 seconds in, the boss will cast Dark Evocation, rezzing all the adds
      • Since you did great and kept them all stacked up, these rezzing adds will all pop up near the front as well
      • Use knockbacks and Vortexes to keep these things at the entrance, and AoE nuke them down ASAP
    • You’ll have the spikes explode about 1:12 into the Stage. You’ll likely be finishing the adds at this point, so make sure if there’s a Barrier, AMZ, or SLT down for the explosion, you’re standing in it
    • About 1:20 in, you’ll get more tank adds
    • About 1:25 in, you’ll get more Oblivion Echos. Again, drop them in the front
    • About 1:30 in, the boss starts to cast the Howling Blizzard
      • The new circle adds will spawn during the blizzard, so do what you can to ensure they stay in the front and have your range kill them
    • We recommend not pushing the boss until after this Blizzard
      • Get him to about 4.5%, then STOP ALL DPS
      • Wait until you’ve been in the phase for 2:10 total, then push the boss into the next Stage 2
    • Repeat this exact process twice
  • Stage 2 (3rd and final occurrence, Remnant 20% > 0%)
    • Here, only send down 4 dps max
    • Everyone else should blast the adds. Remember, the aboms have double the HP as the Banshees, so focus damage on the aboms
    • Communicate between the Phylactery and the top, make sure the adds die about 5 seconds before the Remnant does
  • Stage 3
    • Pop lust immediately when Stage 3 starts
    • If you did push timings correctly, the entire raid should have 2 and 3 minute CDs up here, letting you just melt the boss’s face
    • 20 seconds into Stage 3, the boss spawns adds, including Banshees and Aboms
      • Make damn sure you interrupt the Banshees
      • You will likely want to kill 1 Banshee, but the second just use an interrupt rotation and otherwise ignore
      • Same with the Abom, don’t really worry about him
      • Just nuke DPS into the boss, blast and win
    • After the 3rd Frost Blast in Stage 3, whoever gets it should either immune if possible, or suicide
    • Ggs! Collect your loot, and let’s move on to the Banshee Queen herself