NB: This guide will assume you’ve already read my normal Morchok strategy, or otherwise know the details of the fight on normal mode.
The key difference between normal and heroic mode is that at 90% HP Morchok splits into two clones, one named Morchok and one named Kohcrom, with a shared health pool. Both have the same abilities as on normal mode; Kohcrom does his approximately 6 seconds after Morchok does his, with the exception of the Earthen Vortex/Black Blood of the Earth, which happen simultaneously.
Morchok and Kohcrom both get Furious at 20% HP.
In addition, the Stomp applies a debuff making you take 100% increased physical damage for 10 sec, so you have to split the raid into two teams spread at least 50-60 yards apart (so that one boss’s crystal can’t spawn in the other boss’s Stomp range either) or risk players, especially tanks, being gibbed. There is no Crush Armor, at least!
This splitting of the team requires some thought: in each 5-man team you need a tank plus someone pretty tough to soak the double-hit from the Stomp, which was hitting our Ret Paladin for ~140,000 Physical damage after armour. Rogues can Feint every Stomp, making them excellent candidates, otherwise you’ll need to keep your soaker well topped-off and where possible give them a PW:S too.
On top of that, you need three players to split the damage from the Resonating Crystal. It is unclear whether this targets only ranged players or just ignores the two closest players to the boss, it was merrily targeting someone on the other side of the map rather than picking on the melee DPS soaker if we lost a ranged DPS or healer. You may need to check, and maybe switch an extra melee DPS for a ranged.
A note on composition: we ended up using 4 healers for this encounter, 2 per side. You might be able to lower this eventually but I’d strongly recommend starting with 4 and seeing how you go, even if you get an offspec healer in they’ll be valuable.
Once you have the two teams sorted out, the execution is pretty straightforward, although it is fairly challenging for healers to prioritise healing where it’ll keep people alive – the long-lost art of triage.
There’s a rhythm to the fight, but the most important thing to remember is that every crystal explosion is preceded by a Stomp, so it’s important that when a crystal spawns you wait and soak the Stomp before then running for the crystal. You have roughly 5 seconds to get there, which is easy as long as the tank isn’t miles away from the crystal.
The number one cause of early deaths was people immediately running for the crystal and not splitting the Stomp.
Note that Morchok’s side takes one additional crystal each time, so bear that in mind when planning teams. For example, if your raid has limited mana restoring cooldowns it might be worth putting more on Morchok’s team.
Remember: when a crystal spawns, wait for the next Stomp, then run out to the crystal. You have ~5 seconds to get there, which is plenty of time.
This fight, on heroic, really rewards damage mitigation. I’d recommend a Soul Warding spec so you can cover your entire group, or at least the three people taking the crystal. Archangel/Atonement is less useful here because Prayer of Healing, with the associated guaranteed Divine Aegis absorption, is a much more valuable tool for recovering from and preventing Stomp and Crystal damage. Given the heavy weight placed on PW:S and PoH it’s probably worth glyphing those.
Morchok takes a little over 6 minutes. To get a second PW:B in, you need to use it between the first and second Black Blood phases, and it will be available again during the Furious stage.
Pain Suppression should be used to support your tank and your Stomp soaker during the enrage, when they’ll be taking extra damage from the stomp and may not be able to rotate cooldowns for every one. Earlier in the fight, it can be handy if one person on your team is too low before a damage spike.
Life Grip can save someone’s bacon if they’re slow to run out to get away from the Black Blood or especially if they’re too slow getting in for a crystal.
Finally, the Black Blood phase is a good time to use Hymn of Hope, since there’s no damage caused while you’re safely behind the pillars. Shadowfiend is also safe from the Black Blood because it’s AoE damage, yet Morchok himself can still take damage.
Discipline shines on this fight, because there’s spaced-out damage spikes.
Make sure you PW:S the Stomp soaker and use a few casts of PoH to stack Divine Aegis before the Stomp, then while running to the crystal you can get PW:S on the three people that will take the damage. Once you’re back by the boss and in the ~8 sec lull before the next Stomp, bring everyone back up with Binding Heal and PoH in preparation for the next round.
Binding Heal is a real gift on this fight too, it really helps keep you alive while healing other people and it’s a nice quick cast for triage purposes.