Lead-up: defend allies and escort troops through Nayos, closing rifts and defeating Kryptis champions in each area before reaching Eparch's lair.
Siege Zakiros: use your Skyscale to drop bombs on pylons to clear the malignant fog, then destroy extractor towers with thrown bombs.
Defeat Gatekeeper Vialgos to enter the twin spires; allied forces split between Spire of Redemption and Spire of Creation.
In Spire of Redemption: descend, free prisoners, and defeat Karax the Harvester. In Spire of Creation: descend, clear abyssal watchers, and defeat Charybda the Cunning.
Finale - Defeat Eparch, the Consumed King: focus adds and close rifts fast; open rifts give him barrier and stacking damage/healing buffs.
Grab buff pools: Swords boost power DPS, Fists boost condi DPS, and the green skull grants heavy life-leech sustain.
Players sent to the shadow realm should avoid AoEs and cleanse the damage debuff at fountains on arena edges after returning.
At ~20% HP, clear remaining rifts quickly, then burn Eparch while cleaving adds. If multiple rifts are active, focus them first to prevent buff stacking.
If downed or dead, use ley-lines near the emergency waypoint to glide back into the arena quickly.