Overview
The three tortollans do not share health. Cleave two at a time, usually Nama with whoever you are currently feeding, and keep the third more than 30 yards away. If all three stand together, United Defense cuts their damage taken by 99%. Balance their health and kill them in the same window. A single early death enrages the other two. Lust on pull.
Gebbo throws junk crates. Stomp them for Grab Fish and a stacking Splinters bleed that hits hard, so do not ignore the DoT while you hunt the fish. Carry the fish into melee of the explorer you want and press the extra action at roughly 90-95 Mor'zahi energy. That triggers that boss's ultimate and applies Disgusting Fish, so they cannot be chosen again. Miss the feed and Final Ascension wipes the raid. Feed Gebbo first, then Nama, then Iku.
The council
Nama's Shell Spin is a three-shell frontal aimed at a random melee. Melee stay glued to her and bait it off the platform, then step out. It does not overlap Mighty Thud. Iku's Icebound Flames needs a two- or three-person kick rotation. The tank can help when they are in range. Blink Nova teleports Iku onto a ranged player and splits less damage the farther you run, so do not hug him.
Tanks swap after each Shredding Shards from Iku. Nama's Steady Strikes ramps on whoever she is hitting, so the Nama tank holds personals at high stacks and moves her between Gebbo and Iku so you always cleave two without stacking all three. A death on Iku can cascade into Cataclysmic Invocation. A death on Nama can trigger Relentless Escalation. Assign crate stomps so Splinters does not sit on the same players who are also carrying the fish.
Gebbo: Explosive Surprise
Explosive Surprise lights bomb players while bouncy mushrooms spawn. Drop bombs on the rim, away from mushrooms. A Blast Wave then sweeps the floor. Wait until it is about to hit a mushroom and jump it. Mushrooms are consumed, but several people can use one if they enter together. Jumping a mushroom early strands the back of the raid.
Nama: Mighty Thud
Mighty Thud marks three players. Nama leaps in distance order. Each landing splits Physical damage in 6 yards and knocks. Place one soak in melee and two at separate ranged spots so the circles never overlap. Two teams (odds / evens) is enough: team one takes leaps 1 and 3, team two takes leap 2. Empty landings hit the whole raid.
Iku: Frostfire Volley
Frostfire Volley fires Fire missiles (ranged) and Frost missiles (melee) that must be spread to the rim. Each drop leaves a patch plus Burning Flames or Piercing Frost. Running the opposite element clears a patch and pulses the raid, so plan a healer cooldown for it. Do this last so you are not still soaking Mighty Thud inside fire.
By role
Tanks
Cleave Nama with one other explorer and keep the third more than 30 yards away. Swap Shredding Shards. Move Nama between Gebbo and Iku. Do not let all three stand inside United Defense.
Healers
Blink Nova falls off with distance. Ramp Mighty Thud soaks and the Frostfire clear. Splinters from crate stomps is real damage, so do not ignore it.
DPS
Stomp crates, grab the fish, and feed Gebbo, then Nama, then Iku before Final Ascension. Splinters stacks while you do that, so rotate stomps. Interrupt Icebound Flames. Bait Shell Spin. Soak Mighty Thud as assigned. Cancel Frostfire patches with the opposite element.
Why pulls die
Final Ascension completing is the hard wipe. An early explorer death enrages the other two. Empty Mighty Thud leaps, overlapping Blink Nova, and uncleared Frostfire patches create the mid-fight healing spikes. Tank deaths are Steady Strikes left to ramp. United Defense looks like the bosses simply stopped dying. Ignoring Splinters while you hunt the fish is how people drop before the feed.
Questions
How do you stop Mor'zahi?
Stomp Gebbo's junk for Grab Fish and feed it to the possessed explorer at 90-95 energy. That spends their ultimate and applies Disgusting Fish. Missing the feed lets Final Ascension finish.
Why do the explorers become immune?
United Defense grants 99% damage reduction when all three stand within 30 yards. Cleave two and keep the third farther out.
What is the feeding order?
Feed Gebbo first, then Nama, then Iku. Lust on pull so the last ultimate happens on a dying Iku, not a full-health council.
Do they have to die together?
Yes, or very close. They do not share health, but each death enrages the survivors. If you have to stagger, kill Gebbo first, then Nama, then Iku.