The most powerful elemental still under Deathwing's sway, Morchok - once a passive guardian - is now convinced that his only respite will come with Azeroth's demise. Morchok rages against the foundation of Wyrmrest Temple, Azeroth's last beacon of hope in the Hour of Twilight.
Dragonflight
This section concerns content related to Dragonflight.
Stomp — Morchok performs a massive stomp, splitting 750000[note 1] damage between all enemies within 30 yards. The two closest targets take a double share of the damage. In Heroic Difficulty Stomp also increases the Physical damage taken by affected players by 50% for 10 sec.
Crush Armor — Morchok strikes his current target, inflicting 120% normal melee damage and reducing the target's armor by 10% for 20 sec. This effect stacks up to 10 times. Morchok does not use this ability on heroic mode.
Resonating Crystal — Morchok conjures an explosive crystal onto the battlefield that explodes after 12 sec. for massive Shadow damage. The explosion splits the damage between the three (seven in 25-man) closest players, and the total damage inflicted increases the farther away each player is from the crystal.
Furious — At 20% remaining health, Morchok becomes furious and increases his attack speed by 30% and his damage inflicted by 20%.
The Earth Consumes You! — Morchok uses the power of the earth to draw all players to him, inflicting 5% of their total health as Physical damage every sec. for 5 sec. While the power of the earth draws the players to him, Morchok also summons Earth's Vengence.
Earth's Vengence — Shards of Earth's Vengence erupt from the ground, inflicting 15000[note 2] Physical damage to nearby players within 2 yards and leaving behind obstacles.
Black Blood of the Earth — Morchok causes the Black Blood of the Earth to erupt outwards from him, inflicting 5000[note 3] Nature damage and increasing Nature damage taken by 100% every sec. while a player stands within the blood. This effect stacks up to 20 times.
Kohcrom — Upon reaching 90% remaining health, Morchok tears himself in half and creates his twin Kohcrom. He casts the same spells as Morchok, but a few seconds later.
Magma Flow — Spews out lava for 6 sec periodically, inflicting 15 Fire damage to enemies within 0 yards of the impact. Pulls in all enemies within 100 yards inflicting 4 Fire damage every 1 sec for 6 sec.
Stomp — Inflicts Physical damage to all enemies within 0 yards and knocking them back.
Touch of Flame — Melee attacks have a chance to inflict Fire damage.
Two tanks are required for this fight. Morchok will constantly use 'Crush Armor' on his current target. To remove this, simply have the off-tank taunt when the tank gets the first application and then just continue to tank-swap when the debuff fades off.
Everybody in the group needs to stay close to the boss in order to spread his 'Stomp' ability's damage evenly, but the two tanks must ALWAYS be the closest to him as the two closest targets will take double damage.
When Morchok spawns a Resonating Crystal, three players need to run up to the orb and wait there until it explodes. The laser that links the player to the orb will turn blue when the player is close enough to the orb. Make sure that the orb is close enough to the boss so that the stomp damage is still spread to everyone.
After two Resonating Crystals explode, Morchok will engage Phase 2. Morchok will draw everyone to him, stunning everyone and dealing minor AoE damage. He will also drop spikes everywhere around him. Once the stun wears off, everyone must run to one of these spikes and hide behind them, making sure they stay out of the black blood he spreads everywhere. If you stand in this blood for too long, you will die. Once he finishes channeling the blood, he will immediately stomp, so no one should run back in until he casts this or players will very likely die. When he finishes his stomp, everyone should hug the boss (the two tanks still being closest to him) and repeat Phase 1.
Morchok's attack pattern is very straight forward:
At 20% health, Morchok will enrage and deal a lot more damage. All major cooldowns should be saved for this phase as the damage he deals becomes quite high.
Heroic
Shortly after the first stomp Morchok splits into two bosses (the new one is named Kohcrom, how imaginative). Since both bosses do Stomp and Resonating Crystal, it is best to separate them, with one 5-man team responsible for each of the two bosses. In order to have enough space for the fight you will have to clear some trash on either side of the lane that is usually ignored in normal mode.
The first resonating crystal "belongs" to the Morchok team. The Kohcrom tank should drag the boss out of range while the Morchok team deals with it.
Splitting the raid also means that a non-tank will endure the enhanced Stomp damage from being closest to the tank. Assign a specific player with good movement ability and survivability the job of stacking on the tank so that the damage will be predictable. The other 3 members of the 5-man team will have to stack on the Resonating Crystal to minimize the damage. To make sure that all of the 5-man team is in range of the stomp, the tank should run toward the resonating crystal as soon as it spawns. Positioning the boss close to the crystal is necessary if there are any melee players in the team.
The bosses typically toss their resonating crystals farther and farther from the starting point of the battle. The black blood phase is a convenient time for the team to retreat to the center of the battlefield, reset Morchok's position, and prevent the battle from creeping into adds.
Do not be afraid to experiment with a 3-healer or 4-healer setup.
Loot
Each boss in the instance has their own drops and a table of shared items that can drop off any boss except for both Deathwing encounters.
Morchok
Icy Veins Comprehensive Morchok strategy guide (includes perspective guides for tanks, healers, and DPS, and Heroic mode)
Morchok
Stomp — Morchok performs a massive stomp, splitting 750000[note 1] damage between all enemies within 30 yards. The two closest targets take a double share of the damage. In Heroic Difficulty Stomp also increases the Physical damage taken by affected players by 50% for 10 sec.
Crush Armor 
— Morchok strikes his current target, inflicting 120% normal melee damage and reducing the target's armor by 10% for 20 sec. This effect stacks up to 10 times. Morchok does not use this ability on heroic mode.
Resonating Crystal 
— Morchok conjures an explosive crystal onto the battlefield that explodes after 12 sec. for massive Shadow damage. The explosion splits the damage between the three (seven in 25-man) closest players, and the total damage inflicted increases the farther away each player is from the crystal.
Furious — At 20% remaining health, Morchok becomes furious and increases his attack speed by 30% and his damage inflicted by 20%.
Earth's Vengence — Shards of Earth's Vengence erupt from the ground, inflicting 15000[note 2] Physical damage to nearby players within 2 yards and leaving behind obstacles.
Black Blood of the Earth — Morchok causes the Black Blood of the Earth to erupt outwards from him, inflicting 5000[note 3] Nature damage and increasing Nature damage taken by 100% every sec. while a player stands within the blood. This effect stacks up to 20 times.
Kohcrom 
— Upon reaching 90% remaining health, Morchok tears himself in half and creates his twin Kohcrom. He casts the same spells as Morchok, but a few seconds later.
Magma Flow — Spews out lava for 6 sec periodically, inflicting 15 Fire damage to enemies within 0 yards of the impact. Pulls in all enemies within 100 yards inflicting 4 Fire damage every 1 sec for 6 sec.
Stomp — Inflicts Physical damage to all enemies within 0 yards and knocking them back.
Touch of Flame — Melee attacks have a chance to inflict Fire damage.
[70B] 
[Chest of the Corrupted Conqueror]
[Crown of the Corrupted Conqueror]
[Gauntlets of the Corrupted Conqueror]
[Leggings of the Corrupted Conqueror]
[Shoulders of the Corrupted Conqueror]
Hotfix (2011-12-23): Morchok has been working out, now moves faster in all phases of the fight, and can no longer be kited.